Hello, and welcome to today’s edition of Kitchen Projects.
I am SO thrilled for today’s newsletter as we welcome Sophie Bamford to Kitchen Projects. Sophie is a brilliant pastry chef, also known as All Day Cake. I’ve long marvelled at her brilliance, especially when it comes to cake, and I am SO excited that she has written the buttercream-deep-dive-to-end-all-buttercream-deep-dives for us today.
Over on KP+, Sophie is sharing a stunning recipe for Chocolate Cake With Soy Caramel French Buttercream. It’s time to champion some of those lesser-known buttercreams (no offence, but get out the way, Swiss buttercream!), and I’m so happy Sophie is showing us how it’s all done. Click here for the recipe.
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Love,
Nicola
A Field Guide to Buttercream
by Sophie Bamford
My first encounter with buttercream as a child was helping my mum make a chocolate cake iced with chocolate American buttercream. What greater joy could there be than icing sugar, butter and chocolate combined? This simple buttercream is responsible for beginning my love affair with cake.
Since then, I’ve expanded my buttercream horizons: As a pastry chef, I’ve used a buttload of it over the past 10 years. But even though I’ve used a lot, I’ve never explored every possible option. From Swiss to Ermine, French to German, there’s a whole land of buttercreams out there to explore. Today, we’ll thoroughly investigate each type to understand why some are more popular than others, which is the best vehicle for flavour and what the pitfalls are (and how to avoid them). Think of this as the ultimate head-to-head of buttercreams, a fight to the buttery end to find out which buttercream is “best” (spoiler, there’s no overall winner, and it depends on what you’re making). I’m here to share my findings with you.
Before we begin: What actually is buttercream?
Buttercream’s rise to popularity is relatively recent. Until the 1900s, cakes were almost exclusively decorated with royal icing and marzipan, while biscuits were decorated and filled with royal or water icing. Patisserie featuring buttercream first appeared in Germany around 1915, but layer cakes filled with buttercream didn’t really take off until the 50s, aided by the rise of the home refrigerator.
In its simplest form, buttercream is a combination of butter whipped with sugar, known as ‘American Buttercream’. However, there are many ways to combine these two key ingredients, as well as additional components such as egg and milk which significantly affect the final product. In my career as a pastry chef, I’ve encountered various types of buttercreams, from Italian between layers in an Opera cake to German inside a Paris Brest, French as a macaron filling and Russian on cupcakes.
When I eventually got into making layer cakes, seeing that the majority of professional cake bakers use Swiss meringue buttercream, that’s what I went with. I seem to have been making it on autopilot for years but thinking about it left me with some serious questions:
Why aren’t cake makers exploring the full range of buttercreams? Is Swiss meringue really the best option? Why have I never heard of whole egg buttercream? What’s the best way of adding flavours? How do I get that silky-smooth finish every time? Why does my buttercream sometimes just taste of butter? Which buttercream is going to produce the least amount of washing up?
The Tests
In this post I’m going to give an overview of all the different types of buttercream, what the differences are, why some are more popular than others, how they’re made and rank them against a variety of factors. As it turns out, I have a lot to say on the subject, so look out for an extended multi-part series in my newsletter where I’ll discuss variations and troubleshoot each buttercream individually. I started with a list of all the varieties I could find, then tested them one by one.
The line-up
American: butter and icing sugar whipped together, sometimes with milk or cream.
Swiss meringue: Swiss meringue whipped with butter.
Italian meringue: Italian meringue whipped with butter.
French: made in the same way as Italian but using yolks rather than egg whites.
Whole egg: made in the same way as Italian but using whole eggs rather than egg whites.
German aka mousseline: pastry cream whipped with butter.
Ermine: cooked flour milk and sugar whipped with butter.
Russian: whipped butter and condensed milk.
Now that we know what they are, we can take a closer look at how they’re made and the pros and cons of each. Today, we are going to be using these categories to compare buttercreams and to help us decide which buttercream is right for us:
Taste: The most important! Of course this is subjective so these are just my personal opinions, I’ll be taking into consideration sweetness, flavour and mouth-feel.
Effort: this considers the amount of washing up created and how long it takes to make.
Simplicity: although I believe anyone can make a decent buttercream, if you’re a beginner, I probably wouldn’t start with the most difficult!
Stability: this is how well it holds up. For example, will it collapse if I’m building a tall layer cake, how well will it hold up in higher temperatures, etc? This isn’t necessarily as important on small bakes like cupcakes where the buttercream isn’t load-bearing.
Usability: This somewhat overlaps with stability, but here I’m talking about how easy it is to get that perfectly smooth finish with crisp edges, which, again, is only essential if you plan on using buttercream on a layer cake.
Adaptability: how easy it is to customise the flavour without affecting the texture, stability or to make a plant-based version.
Alright, let’s get into it!
American
American Buttercream is probably the first buttercream you learn how to make. The recipe is straightforward, with zero faff or making of syrups, which is perhaps why it's so popular with home bakers. To make it, simply cream butter until pale and fluffy before adding icing sugar and mixing until smooth. I did a 1:1 ratio for today's tests as I didn’t want it too sweet, but most recipes call for a 2:1 ratio of sugar to butter. Not only does this make it incredibly sweet, it is much more difficult to get a smooth finish. Recipes that add a lot of sugar may also add milk or cream to help dissolve the sugar and make it slightly less granular and more spreadable. This somewhat affects the stability, but overall, I would consider American buttercream one of the most stable out of the buttercreams I’ve tested.
American buttercream is perfect if you’re just starting out, as there’s virtually no room for error. I find the high ratios of sugar slightly too sweet, and some recipes call for so much icing sugar that it develops a slightly gritty texture and even a bit of a crust. I prefer a silkier texture and less sweetness for the cakes I make. Because American buttercream has a very low percentage of water it allows some flexibility when adding flavours. You can add 10-15% of liquids such as fruit purees or creme fraiche to add flavour / reduce the sweetness.
Taste: It can be on the sweet side and has a slightly grainy texture.
Effort: Extremely easy, perfect for beginners, minimal washing up.
Stability: It holds up well in higher temperatures, has a nice firm texture, so it is good for layering in taller cakes, doesn’t split.
Usability: Easy to use as long as there’s not too much sugar in there.
Adaptability: Good for adding purees or other flavouring liquids but not much opportunity to infuse flavours or change the sugar. It can easily be made plant-based.
Swiss Meringue
This is probably the most popular amongst professionals and certainly my most used. It’s relatively easy and makes barely any washing up (always a plus). To make it, we whisk egg whites and sugar over a pan of boiling water (bain-marie) until the sugar is dissolved and the egg whites are cooked to 70°C/158°F. This mixture is whisked into a stiff meringue, and softened butter is slowly added.
This makes a lovely fluffy buttercream. Air is incorporated both in the meringue and in the butter, and because the sugar is fully dissolved, the end result has a lovely smooth texture. Simple variations can be achieved by using different sugars; Made with brown sugar, this buttercream has a lovely depth of flavour that works beautifully with flavours like chocolate and coffee. Although, at first glance, you might think this method is slightly more complicated, I truly believe anyone can do it.
Taste: Lovely, smooth, sweet, light, and airy.
Effort: More steps than other buttercreams but still achievable and worth it for the results, risk of splitting but this can be easily fixed by whipping, just keep going!
Stability: Holds up well in higher temperatures and a nice firm texture, so it good for layering in taller cakes.
Usability: Very easy to use, the best buttercream for getting that silky smooth finish and crisp edges.
Adaptability: Great for switching it up when it comes to dry/ crystalline sugars, also a good option for adding flavourings in the form of purees or curds, like American this buttercream can take 10-15% of its total weight in additional liquid.
Italian Meringue
This buttercream is almost identical to Swiss meringue, the only difference is the meringue method. Italian meringue is made by making a sugar syrup, boiling it to 118°C/244°F and then pouring it over egg whites as they whisk. There is a greater margin for error in this method; you really have to get your temperatures just right, and the sugar syrup can crystallise if you’re not careful. But it does have its perks, my favourite of which is being able to replace the sugar with syrup alternatives, e.g. honey & maple syrup.
This is particularly effective for Italian Meringue buttercream because we evaporate much of the water, resulting in a concentrated flavour without compromising stability by adding more liquid.
Taste: Lovely, smooth, sweet, light, and airy.
Effort: More work and washing up than others, I’d only use this method over Swiss if there was a particular reason to do so e.g. sugar syrup substitutions.
Stability: Holds up well in higher temperatures and a nice firm texture, so it good for layering in taller cakes.
Usability: Very easy to use, the best buttercream for getting that silky smooth finish and crisp edges.
Adaptability: The best option when using alternative liquid sugars or caramel, another good option for adding flavourings in the form of purees or curds, it can take 10-15% of its total weight in additional liquid.
French
French buttercream is made in the same way as Italian meringue, but rather than egg whites, French buttercream uses egg yolks. This changes both the flavour and the texture, the high percentage of fat in the yolks means that less butter is required in order to achieve a good emulsification, however it also means that the egg mixture doesn’t whip up as much or hold air in the same way that Italian or Swiss meringue do, this results in a denser, richer buttercream that can be prone to collapsing and becoming runny if used when too warm, I find the best way to use French buttercream is to chill it after making to allow the butter to fully cool before re-whipping.
With an almost custardy flavour and a soft yellow colour, this buttercream is definitely worth the extra effort. It shines when paired with vanilla, nutmeg, or rum. It’s also perfect if you have a lot of egg yolks to use up.
Taste: Nice custardy flavour, lovely and smooth, richer and more dense than meringue-based buttercreams.
Effort: More work and more washing up than some of the others.
Stability: Doesn’t hold up well in high temperature, can become sloppy, must be used cold, I wouldn’t recommend it for very tall cakes.
Usability: It can be difficult to use, not the easiest for a perfectly smooth finish and crisp edges.
Adaptability: It is not great for adding flavours. It can take a little additional liquid but only around 5%. Like Italian meringue, alternative sugars can be used, but the French buttercream already ha s a distinctive taste, so it wouldn’t be my go-to for incorporating different flavours.
Whole Egg
I don’t know why this buttercream isn’t more popular! I made this when I was in college and forgot about it until writing this piece. Using the same method as Italian and French, this buttercream uses whole eggs whisked until pale and fluffy before boiling sugar syrup is poured over (you might see this referred to as pâte à bombe). Butter is added, resulting in something between French and Italian meringue buttercream, richer than Italian but lighter than French.
This is a really good option if you can’t be bothered to faff around separating eggs. Because the pâte à bombe isn’t as stable as a meringue, this buttercream can be more prone to collapsing, so it will need to be kept in the fridge.
Taste: Lovely and smooth, not too sweet, denser than meringue-based buttercreams.
Effort: More work and more washing up than some of the others.
Stability: Not the best, not the worst, it doesn’t hold up great in high temperature and can be prone to splitting, just whip for longer if it splits but it’s still a viable option for layer cakes.
Usability: Pretty good! It's slightly harder to get perfect crisp edges but easy enough to get smooth.
Adaptability: Because the flavour isn’t as “clean” as meringue-based buttercreams, it’s not my preference when it comes to adding light, fruity flavours, and it can’t take much additional liquid, but like Italian sugar alternatives, it can be used to change the flavour up.
German
German buttercream (also known as creme mousseline) is a blend of pastry cream and butter. To make it, we start off by whipping a thick, chilled pastry cream and adding butter. The pastry cream base results in a nice custardy flavour. Due to the high ratios of liquid, I find this to be less stable than other buttercreams meaning it can be a bit sloppy when at room temperature or inclined to split, which is probably why it isn’t used in layer cakes very often. Despite its flaws, it’s very delicious and the least sweet of all of them (potentially not sweet enough sometimes!). It also provides the opportunity for you to infuse the milk with different flavours before making the pastry cream.
Taste: Nice and smooth, not sweet, custardy flavour, on the denser side.
Effort: A lot of effort washing up, and chilling time is required, not one to make if you’re in a rush.
Stability: Doesn’t hold up well in high temperature, can become sloppy, must be used cold, I wouldn’t recommend it for very tall cakes.
Usability: It can be difficult to use, not the easiest for a perfectly smooth finish and crisp edges, and has a tendency to split.
Adaptability: Great for infusing different flavours in the dairy.
Ermine
Also known as cooked flour buttercream, ermine is similar to German buttercream. However, rather than pastry cream, this buttercream starts with a milk, flour, and sugar mixture, kind of like a sweet roux. It is then cooked to a pudding consistency. The high levels of flour in this buttercream absorb a lot of the liquid as it cooks and thickens the roux, making it slightly more stable than German buttercream.
Once the roux is chilled, butter is whipped in to form a smooth buttercream. This process produces a slight floury flavour, so the milk should be infused for the best results.
Taste: Nice and smooth, not sweet, milky flavour, on the denser side, can taste slightly floury.
Effort: More effort and washing up than others, and chilling time is required, not one to make if you’re in a rush.
Stability: Good stability, holds up well in warmer temperatures, the more flour, the more stable.
Usability: Can be difficult to use, not the easiest for a perfectly smooth finish and crisp edges.
Adaptability: Great for infusing the milk with different flavours. It can easily be made plant-based.
Russian
Made of just two ingredients, this recipe is really easy, this method combines sweetened condensed milk with whipped butter, the result is quite a dense buttercream with a sweet, milky flavour. This is a buttercream that I had never really used before doing these tests. I don’t find this to be very versatile, but if you want your buttercream to taste like condensed milk, then this one's for you!
Taste: Very strong condensed milk flavour, quite a dense texture.
Effort: Very easy, perfect for beginners, minimal washing up.
Stability: Fairly stable, but it wouldn’t be my first choice in warmer temperatures.
Usability: It is fairly easy to use. It is not the best for crisp edges, but it is relatively easy to smooth them.
Adaptability: It is not the best choice for added flavours. The taste is already strong, and it can’t take much additional liquid. Swapping the condensed milk for Dulce de leche is a good option.
Ratios
Having looked at each buttercream individually, we can now compare the butter, sugar and liquid ratios. This can help us to understand why certain buttercreams are more stable and easier to use than others. Buttercream is really a game of ratios: Too much butter and you’ll feel like you’re just eating a block of butter, too much sugar and it’ll be overly sweet, too much liquid and the buttercream won’t emulsify making it incredibly difficult to use and impossible to get that perfect smooth finish. The trick to getting a buttercream that is beautifully smooth and easy to use is having a really good emulsification, for this reason buttercreams with a higher ratio of butter are generally easier to use while buttercreams with a high ratio of liquid are generally more difficult to use.
Other factors, such as starch (which helps absorb liquid and bind ingredients together) and the varying fat content of liquids (e.g., egg yolks, which also help emulsify), must also be considered when creating recipes. For example, higher percentages of protein, like egg whites in our meringue buttercream, help stabilise and incorporate more air.
How to choose a buttercream
When choosing a buttercream the main thing to figure out is what you want from it, do you want to use it to add a specific flavour, do you want it to hold up well in a warm environment? How important is a smooth finish to you? Based on the categories we established earlier, I have created a ranking system of 1-5 cake slices 🍰 (1 = bad, 5 = good).
As well as the factors above, it’s also worth considering the texture of the cake you’re working with; Rich butter cakes tend to work well with slightly more sturdy buttercream like American or Swiss, whilst lighter sponges like genoise or chiffon work best with lighter and less sweet buttercreams like German or Ermine.
A final word of advice: Don’t be afraid to mix and match! Sometimes, there isn’t one single buttercream that is best for the job. I frequently use one buttercream to fill a cake and another to coat. That way, you can use a stable buttercream for the outside (Swiss meringue is my favourite for crisp, clean edges) to lend some additional support, then use another buttercream on the inside for flavour!
Ready for a recipe?
Head over to KP+ for Sophie’s recipe for Soy Caramel French Buttercream and chocolate cake.
It is so helpful to know that you can reduce sugar in American buttercream to 1:1 with the butter. The way most recipes are written it is so sickly sweet. Will definitely try it with less sugar.
Hi Nicola, do you have a recipe for Swiss Meringue Buttercream? Every time I attempt to make it, it turns out differently, and I struggle with either a separated or soupy or air-bubbly frosting. I need help! I want to be able to nail this frosting every time I make it!