Peanut Butter Swiss Buttercream
- Prepare a double boiler or a pot filled with about 2 inches boiling water. If using a pot of boiling water, make sure that your mixing bowl will fit on top of pot without bottom of bowl touching water.
- In a glass or metal mixing bowl, use an electric mixer to whisk egg whites and sugar together until foamy. Place bowl over boiling water.
- Continue whisking with electric mixer until sugar has dissolved completely. This can take up to 5 minutes.
- Transfer mixture to bowl of a stand mixer fitted with whisk attachment.
- Whisk on high speed until stiff peaks form. This may take up to 15 minutes (longer if kitchen is particularly hot and/or humid).
- Switch to paddle attachment. Add vanilla, salt, and peanut butter a spoonful at a time and mix on medium speed until peanut butter is fully incorporated.
- Cut butter into thin slices (about 1/2 tablespoon per slice). With mixer running, add a few slices of butter at a time until frosting is smooth and creamy.
- If frosting is too thin, put bowl in refrigerator for 20 minutes. Return to mixer and beat until smooth.
Recipe developed for Imperial Sugar by Ashton Swank @somethingswanky.
For a smooth and creamy buttercream frosting, all ingredients should be at the same temperature. If your liquid was not at room temperature the mixture cannot homogenize and will take on a curdled appearance (become soupy looking). This is a sign that the mixture is still too cold. Rapidly stirring and gentle warming will emulsify the buttercream to a smooth and creamy consistency. Continue to mix while using a hair dryer on the outside of mixing bowl until the perfect consistency is reached. For additional tips on how to make the perfect buttercream, watch our How to Fix a Broken Buttercream video.