French buttercream is a frosting made from eggs, sugar, water, butter, and flavor, such as vanilla extract. If you can make Swiss meringue buttercream, you can make this frosting easily; the egg mixture is similarly cooked over a water bath and mixed with softened butter. The final frosting is fully-cooked and pale yellow in color with a rich buttery vanilla flavor that frosts smoothly onto cakes and pipes intricate designs.
My recipe uses whole eggs, unlike most traditional French buttercreams that use just yolks. I like that it is ingredient-efficient; no need to find a use for all those extra egg whites like in traditional French buttercreams. I also use a simmering water bath (as used in the Swiss meringue method) to cook the egg mixture rather than pouring in hot sugar syrup (as with Italian meringue). I found this method to be a tad easier and did not affect the overall texture of the finished buttercream.
Because of this and the use of whole eggs, my French buttercream is slightly less yellow than traditional French buttercreams. And don’t worry about it tasting “eggy” - that’s not how I would describe the flavor. You taste more of the sugar and butter, and it’s more “custardy,” and you can always increase the vanilla extract at the end.
Whole eggs give this frosting flavor, color, structure, and moisture. Most French buttercream recipes use just yolks, which are yummy too, but when we add the whites to our buttercream, we add extra proteins (structure) and water. Like a Swiss meringue, we’ll cook the eggs, water, and sugar atop a simmering water bath. But unlike a Swiss meringue, you’ll notice they won’t whip up as high as a pure egg white meringue during the whipping step. The fat from the yolks disrupts the egg white and yolk protein’s ability to capture air bubbles.
White granulated sugar will dissolve into the water contained in the eggs (plus the extra we've added) to contribute to this buttercream’s delicious sweet taste.
Water is needed to help dissolve the sugar in the egg mixture.
Unsalted butter contains the majority of the fat for this buttercream. It also includes a particular protein called an emulsifier, which holds fat and water-based ingredients together. This is super important since this buttercream is emulsion-based. I always use unsalted butter in my buttercreams as salted can vary salt levels on the particular brand and make your final buttercream overly salty.
Vanilla Extract/Salt provides the overall flavor profile of the finished buttercream. Any extracts can be used, but my recipe below is vanilla.
Step 1: Prepare the double boiler.
Add water to a pot that can hold your stand mixer bowl. Bring water to a gentle simmer.
Step 2: Prepare egg mixture.
Add eggs (2a), sugar, and water (2b), to your stand mixer bowl and stir together with a spatula (2c).
Step 3: Cook eggs.
Place the egg-sugar mixture atop the simmering water (3a) and cook until it reaches 165°F (3b).
Step 4: Whip up the egg mixture.
Place the bowl on the stand mixer and whisk (4a) until it’s thickened, about 10 minutes (4b).
Step 5: Add butter.
Add softened butter one tablespoon at a time (5a) and whisk until combined (5b).
Step 6: Flavor and smooth out.
Switch to the paddle attachment and mix on low speed (6a) until smooth and creamy (6b).
Almost all of my frostings can be found in my cakeculator, which allows you to customize your frosting flavors and amounts based on the cake you're baking. The frosting recipe below makes 1 or 3 cups, but if you need another quantity, go to my Cakeculator here and choose "Vanilla French Buttercream".
IMPORTANT NOTE: You can perfectly replicate all my cake and frosting recipes using gram measurements. Weighing is the most accurate way to bake and I use it exclusively.
For American bakers, I have converted grams to estimated volumes (cups, teaspoons, etc.), which are not as accurate and may have awkward proportions, but they still work.
For 1 cup of buttercream (great for testing out this recipe)
For 3 cups fo buttercream