This mint Swiss buttercream tastes like a butter mint but in smooth, silky buttercream form. A wonderful frosting for almost any chocolate or mint cake, it goes especially well with my mint chocolate sheetcake recipe.
6-8drops mint oilor 1/2-1 teaspoon of mint extract, to taste
1poundbuttersoft but still cool
2-4drops green food coloringoptional
Instructions
Combine egg whites, sugar, and salt in the bowl of your stand mixer.
Place it in a pan with about 1-1 1/2" water in it. The pan should be large enough that the bottom of the bowl fits in but small enough that the bottom of the bowl does not hit the water.
Heat over high heat until the water comes to a boil, whisking the mixture constantly.
Once the water boils, regulate the temperature to maintain a high simmer, and continue to whisk the whites until the sugar is completely dissolved and the mixture is at least 140F. You can continue to cook and whisk until the temperature gets as high as 180F. I like to whip mine to 165F, but as long as the sugar is completely dissolved, you are good to go.
Once your whites have reached the desired temperature, remove the bowl from the pot and fix it to your stand mixer, fitted with the whisk attachment.
Whip on medium high to high speed until room temperature.
Add the butter, about 1 tablespoon at a time, beating the mixture until the butter is completely incorporated before adding the next addition. (NOTE: Please watch the video. You don't want to rush this process. Also, the meringue will break down from the fat and get soupy. Don't worry. It will come together in a beautiful, silky buttercream that holds its shape by the time you add in all the butter.)
Beat in the peppermint oil and green food coloring (if using). Note that the color will intensify overnight, so to keep the green subtle, lean more towards less food coloring.
Video
Notes
To Store:
Keep in a sealed container at cool room temperature for two days. Store in the fridge for up to a week. Freeze for up to 3 months.In any case, bring to cool room temperature before rewhipping to restore the silky texture. Once the cake is frosted, I store it in the fridge, allowing each slice to temper on the counter for 20 minutes or so before eating.NOTE: Nutritional information based on 24 servings.