Kitchen Project #165: Coffee Cake

Bronwen Wyatt takes on the classic

Hello,

Welcome to today’s edition of Kitchen Projects. Thank you so much for being here.

Today I am thrilled because Bronwen Wyatt is back! Here to take on another american classic - this time, it’s Coffee Cake. From segues into the pros (and cons) of cake flour, to Bronwen’s fabulous ‘matrix of despair’ (UK readers - a forewarning. This cake contains no coffee. Get with the programme) it’s a wonderful ride resulting in the most beautiful, plush cake that you should make right away.

On KP+, Bronwen has shared an ingenious pastiche for the classic - coffee cake scones, fit with with ribbon of cinnamon butter. Click here for the recipe.

What’s KP+? Well, it’s the level-up version of this newsletter. By joining KP+, you will support the writing and research that goes into the newsletter (including the commissioning - and fair payment - of all the writers), join a growing community, access extra content (inc., the entire archive) and more. Subscribing is easy and only costs £6 per month or £50 for the whole year. Why not give it a go? Come and join the gang!

Love,
Nicola

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All About Coffee Cake

by Bronwen Wyatt

It’s hard to think of a more pervasive American breakfast pastry than coffee cake - you’re as likely to find it in a southern church basement as a New York deli counter. Whether baked in squares or rings, they are united in the two main points. The cake must always have streusel of some type, and the primary spice must be cinnamon. What it almost never contains, outside of the tongue-in-cheek modern twists on the classic recipe, is coffee. Coffee cake is meant to be enjoyed with coffee, in the morning or as a midday snack. Someday I may write a thesis on how cinnamon is the key that gives us cultural permission to eat dessert for breakfast: cinnamon rolls, cinnamon sugar donuts, coffee cake itself.

Nearly everyone agrees that American-style coffee cake was introduced by immigrants from Northern Europe and Germany, who brought the tradition of enjoying coffee with cake with them wherever they settled. This is perhaps a key to the ubiquity of coffee cake in places as disparate as the Midwest, home to so many people of Scandinavian and German descent, and the urban sprawl of the Northeast and its Eastern European Jewish diaspora.

Coffee culture in Europe has a long and winding history. The first coffeehouses (as we think of them now) were in Syria, and the culture later spread throughout the Ottoman Empire and from there to Europe. In Vienna, the epicenter of European coffeehouse culture, the first coffeeshop may have been started by a Polish diplomat in 1683, or an Armenian merchant in 1685, depending on who you ask. Viennese coffee culture was even declared a UNESCO “intangible cultural heritage” in 2011. I remember learning about it in high school - how the intellectual and political elite of Europe gathered in Viennese-style coffeehouses, giving birth to new movements of thought in science, literature, and art over coffee and cake. Across northern Europe and Germany, the cultural practice of taking a break for coffee, sweets, and gossip has its own vocabulary: fika in Sweden and Finland, kaffepause in Denmark, kaffeeklatcsh in Germany, or koffiepauze in the Netherlands. The first coffee cakes were sweet yeasted breads, sometimes with fruit, often with a crumb topping. Stories vary on the source of these first European coffee cakes, though most point to the German kaffeekuchen or streuselkuchen. Streusel, after all, comes from the German word “to strew”, or to scatter.

The cake of the modern coffee cake is nearly always a butter cake enriched with sour cream. Reviewing a broad swath of recipes, the percentages hover between a classic butter cake and a pound cake. This makes sense - the cake needs to be tender, but sturdy enough to support the weight of a layer of streusel. You might occasionally see an oil-based coffee cake, but these are the exceptions. A quick note: Nicola mentions that in the UK, the most “classic” butter cake ratios are closer to pound cakes. In the US, we tend to think of traditional cakes like yellow cakes as a “butter” cake, which are lighter than a pound cake.

The streusel texture of coffee cake ranges the gamut from thin sheets of sugary sand to pebbles nearly 2.5 centimeters in diameter. It might, or might not contain nuts, almost always soft, fatty pecans or walnuts. Sometimes the streusel tops a layer of fruit - usually the dependable apple, occasionally blueberry. Sometimes the cakey center is ribboned with a swirl of additional cinnamon, like a layer of sediment in a geological specimen. Other times a thinner layer of cake is mounded with clumps of streusel taller than the cake itself.

The latter is called “New York-style crumb cake”, the pride of New England -except when in New Jersey, where it’s called “New Jersey-style crumb cake” or even more oddly, a “crumb bun”. Fans argue bitterly over where to get the best version, though B&W Bakery in Hackensack, New Jersey is often at the top of the list. Sources frequently cite the 2000 lbs of crumb topping that is used a week at B&W. I ordered one to try and was surprised to discover they still use a yeasted dough. In the Midwest, Cincinnati, Ohio is sometimes cited at the coffee cake capital of the world, in part due to its own German heritage. From my own observation, I’d argue that Midwestern coffee cakes are more likely to be baked in rings or bundts, while Eastern coffee cake is always a rectangle or square.

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My Coffee Cake Quest

I knew immediately when Nicola asked me to develop a coffee cake that I wanted it to be an exquisitely classic version: no fruit, simply flavored with cinnamon, brown sugar, and vanilla. I wanted rather a lot of streusel that was firm on the outside but yielded when bit into a pleasantly soft texture. So much streusel is too crunchy! The streusel also needed to vary in size, ranging in shape from coarse cornmeal to peas - a textural playground. Last, I wanted the classic marble of cinnamon filling through a soft, tender cake - I’d leave the NY style crumb cakes aside for now.

Typically when I start off a project bake like this, I’ll pull a recipe from my arsenal and adapt it so that I have something to compare when I’m making alterations. I took a butter cake recipe, swapped out buttermilk for sour cream, layered a cinnamon sugar filling inside, and made a simple streusel with dark brown sugar to top it.

To be honest I think my first version is where many online recipes begin and end - but it wasn’t very good. I wasn’t sure the sour cream added much to the flavor, and both the streusel and the cake were too dry. To be completely honest, after reviewing the fat content and baking times of a score of crumb cake recipes online, I think we are facing an epidemic of dry coffee cakes in this country. No matter - I would play with the percentages in both the butter cake and the streusel until I hit the perfect combination.

Over on KP+, Bronwen is sharing an coffee cake adjacent bake in the form of Coffee Cake Scones. Meltingly tender with a crunchy streusel and a ribbon of cinnamon running through the middle:

The Matrix of Despair

I was so naive! Here is where I entered what I shall now call: the Matrix of Despair. Nicola has her matrix of joy (see: Sift). You see, I wanted to test the differences between versions of streusel at the same time I tested tweaks in the cakes. This produced a complex web of minute alterations that were difficult to track and that all affected each other in ways that were hard to predict. (For the sake of my sanity, I focused on the cake and the crumb in my initial tests - I’d work out the ribbon of filling when I had those settled).

Here’s an example: one crumb cake I made, using the creaming method and substituting acidulated heavy cream for sour cream, proved too tender to support the weight of the streusel. The cake itself was delicious but the streusel sunk in and visually it wasn’t the look I was going for. The cake on the left also needed to bake for 45 minutes - the added streusel adding significant length to the bake time. The cake on the right - the exact same cake ratio - baked for only 30 minutes, resulting in a much more tender crumb. I couldn’t test the cakes without also testing the streusel. (picture here)

But different streusels also behaved differently - above, you can see a version I made with molasses (to boost the brown sugar flavor) sunk significantly into the buttermilk batter. Was the streusel too heavy, or was the thinner buttermilk batter not supportive enough for the streusel? To test all possible variations together would require making 81 crumb cakes - and though I do my tests in a much smaller size, this seemed too much even for the thorough Kitchen Projects. I would have to weed out underperforming cakes and streusels viciously in the quest for my ultimate final bake.

The versions I made with yogurt and buttermilk were immediately out of the running. The long bake time of a coffee cake (remember the added bake time from the streusel!) demanded more fat to ensure tenderness in the final product. A version I made with both butter and oil similarly fell flat - the moisture level was nice, but the flavor was lacking. Simply adding more butter did produce a more tender cake, but it wasn’t enough to combat the longer bake time of the coffee cake.

I knew I wanted a lightly acidic dairy to balance the sweetness in the coffee cake, and to help boost the rise and tenderness in concert with a little added baking soda. I tried blending sour cream with heavy cream (with decent results) before settling on acidulated heavy cream for my dairy - the results were decadently rich and tender. I experimented with adding both lemon juice and apple cider vinegar, and found both to work well without imparting a noticeable lemon or vinegar flavor - I use 2 teaspoons lemon juice or vinegar to 175 grams cream I did not experiment with creme fraiche - at least here in the South, creme fraiche is hard to buy, and homemade versions are just acidulated heavy cream anyway (rather than proper cultured creme fraiche).

Where I admit I (mostly) hate cake flour

The next step in my quest for ultimate coffee cake tenderness was to try out cake flour. Cake flour is used a lot in the States for classic layer cakes - you often see it called for in basic yellow cake recipes. I’ve always had a complicated relationship with it, though. Cake flour, with its low protein content, is great for tenderness, but its finely milled grains can lead to a powdery flavor in the crumb of a cake that I find particularly hard to ignore. Even balancing the ultra-absorption properties of fine-grained, thirsty cake flour with a little extra liquid can’t quite hide it for me. You can’t deny it produces a plush crumb, though - and here you can see how its ability to absorb liquid leads to a much taller cake with more doming. Doming is fine in many contexts, but with a crumb cake it tends to shove all the crumb to the edges, and I wanted a more even distribution.

I even tried a reverse-creamed version, which often reduces the doming of cakes, with a little extra liquid to combat the cake flour. The result was a nice crumb distribution and a very plush crumb - one tester remarked it tasted like Entemann’s, the gold-standard supermarket crumb cake. But I still couldn’t get over the powdery feel - as if you were tasting a cornstarch sponge. Splitting the difference solved the problem - using 50% cake flour and 50% all purpose produced a very tender cake without nails-on-a-chalkboard flavor of 100% cake flour. I tested my new flour ratio with both creaming and reverse-creaming and settled on the latter method. Popularized by the notorious RLB (the great Rose Levy Berenbaum), reverse-creaming has you blend your dry ingredients with butter before adding your wet ingredients, producing a remarkably even crumb and soft, but sturdy cake.

A note on sourcing flours

As a baking professional, I was taught that cake flour had the lowest protein content, followed by pastry flour, all-purpose flour, and bread flour. Confusingly, there isn’t a strict standard for the protein content of flours between brands. I tested this recipe with Swan’s Down cake flour (listed as 6-8% on their website) and Central Milling Company All Purpose Flour (10.5%), which I buy in bulk at Costco. Hot tip- in the US, the Costco organic all purpose flour is from Central Milling, even if it has the in-house branding. King Arthur, a popular flour company in the States, actually lists their pastry flour as having the lowest protein content (8%), followed by cake (10%), all purpose (11.7%), and bread (12.7%). I think it’s fascinating that the percentage of gluten-forming proteins between the KA all-purpose and bread flour is just one percent - roughly the same percentage point difference between Central Milling and King Arthur all-purpose flours. These numbers may be small but they make a real difference! If you’re in the US and looking for a supermarket brand with similar protein percentages as Central Milling, Gold Medal all purpose flour also rings in at 10.5%.

So what to do if cake flour isn’t readily available in your market, as I’ve recently learned is true in the UK? I’d try these recipes with the lowest protein all-purpose flour you can find. Frustratingly, not all brands label the protein content of their flours (and some have variable protein content between batches - Rose Levy Berenbaum has a fascinating blog post on this). Ultimately, you can still make a delicious cake with the all purpose flour that is available to you!

The streusel situation

I used a similar approach to nailing the streusel texture. Using 100% cake flour produced a soft, tender streusel, but it didn’t hold its shape well, melting into blobs on the surface of the cake even when I froze the streusel before applying. Ultimately I settled on half all purpose flour to half cake for a streusel that held its shape, and had a crisp exterior and soft interior. Both light and dark brown sugar produced tasty streusels - I ultimately settled on dark brown for the boost of flavor, but it was close - either dark or light brown sugar will work well throughout these recipes. A little granulated sugar in the streusel prevented it from being too chewy. My molasses experiment was an utter failure - even just a tablespoon in the streusel made it have a gluey texture.

I use a very fresh, very potent cinnamon from Burlap and Barrel in my baking (though I’ve tried delicious cinnamon from other small brands as well). The cheapest cinnamon on the supermarket shelf had an almost sawdust flavor and unappetizing, slightly acrid smell. When using a fresh, bright cinnamon, two teaspoons in the streusel was more than enough.

The final cake failure

Once I had settled on my ultimate streusel and cake combination, I baked a large-format version in the 8” x 8” pan I’d be using for the recipe. To my horror, the streusel sunk into the center of the cake as it baked. When testing this recipe in a much smaller pan, as I do for my initial tests, the cake had plenty of support and the streusel remained in a nice even layer on top. Slicing into the cake, I noticed that the ribbon of brown sugar and cinnamon I’d sprinkled into the center of the cake had sunk to the bottom. My denser cake layers in my very first test had no trouble supporting either the filling or the streusel, but this version was so delicate it could do neither well.

The solution, of course, was to be found in The Cake Bible, Rose Levy Berenbaum’s magnum opus. She sprinkles her streusel on her coffee cake halfway through baking to ensure it doesn’t sink, and uses less filling over all as well. I decided after some tinkering to marble my cinnamon-sugar filling to create appealing little pockets of flavor throughout the crumb of the cake. A little bit of cocoa powder in the filling boosted the color.

RECIPE: Classic Coffee Cake

For the streusel:

• 95 g dark brown sugar

• 25 g granulated sugar

• 75 g all purpose flour

• 75 g cake flour

• 2 teaspoons cinnamon

• 1/4 teaspoon kosher salt

• 100 g butter, room temp

• 1 teaspoon vanilla extract

For the filling:

• 40 g/ 3 tablespoons dark brown sugar (40 g)

• 1/2 teaspoon cinnamon

• 1/2 teaspoon cocoa powder (optional)

For the cake:

• 175 g heavy cream

• 2 teaspoons lemon juice or vinegar

• 2 teaspoons vanilla extract

• 200 g granulated sugar

• 100 g cake flour

• 100 g all purpose flour

• 1 teaspoon baking powder

• ½ teaspoon kosher salt

• 1/4 teaspoon baking soda

• 170 g butter, room temp

• 100 g whole eggs (from about two), room temperature

Method

• To make the streusel: Combine all the dry ingredients in the bowl of a stand mixer and whisk to combine. Add the soft butter, cut into rough chunks (it’s important to the texture of the streusel that the butter is quite soft - around 75 degrees Fahrenheit / 24 C).

• Mix on medium speed with a paddle attachment until small, pebbly crumbs form, about one minute. Scrape down the paddle of the mixer. Drizzle in the vanilla extract and continue to mix until the streusel looks more hydrated (less powdery/sandy) and has begun to form larger pebbles - this should only take about another minute. If you’re using only all-purpose flour here, you may need to drizzle in 1-2 teaspoons of water to get the streusel to the proper texture - see the photo for an example of what we’re looking for.

• Spread into a single layer on a small baking tray and pop into the freezer until ready to use.

• To make the filling: Whisk all the ingredients in a small bowl and set aside.

• To make the cake: Preheat the oven to 350 F (176 C / 160c fan, though I recommend no fan if possible).

• Line an 8” x 8” baking tray with parchment paper and pan spray and set aside.

• Combine the lemon juice or vinegar and cream and stir. Add the vanilla, stir, and set aside while preparing your other ingredients.

• Combine the sugar, all purpose flour, cake flour, baking powder, baking soda, and salt in the bowl of a stand mixer and give it a thorough whisk to combine.

• Crack the eggs and set them aside in a separate container.

• Add the softened butter, cut into chunks, into the dry ingredients. Drizzle half the cream over the dry ingredients. Combine the remaining cream and the eggs and give them a little stir to break up the yolks, and set aside.

• Blend the dry ingredients, butter, and cream together on low speed for 30 seconds with a paddle attachment. Stop and scrape down the sides of the bowl and the attachment. Continue to mix on medium speed for one minute and thirty seconds.

• Add half of the remaining yolk/cream mixture and continue to mix on medium speed for one minute. Scrape down the sides of the bowl and the paddle attachment. Add the final portion of egg/cream mixture and mix for an additional minute.

• Remove two-thirds of the batter from the mixing bowl (about 560 grams) and spread it in an even layer in the prepared cake pan. Sprinkle the filling on top. Dab the remaining batter over the filling and spread it to the edges. Swirl a toothpick or narrow knife through the batter to marble it in.

• Bake the cake for 35 minutes. The edges should be puffed and just beginning to turn golden. Quickly and carefully remove the cake from the oven and sprinkle the cold streusel on top, focusing on the borders of the cake rather than the center (piling too much streusel in the center may cause it to sink a little). Bake the cake for another 25-35 minutes, or until a knife inserted in the center comes out with only a few stray crumbs attached. The streusel on the center cake may have a slightly damp sheen still - that’s okay.

• Allow to cool for at least half an hour before slicing. The cake will keep, wrapped tightly at room temperature, for three days.

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Keep up to date with Bronwen’s bakes and writing here on substack and over on Instagram @bayousaintcake