135 grams powdered sugar, sifted if lumpy, plus more as needed
60 grams heavy cream, at room temperature, plus more as needed
1/2 teaspoon vanilla extract
Instructions
Using a handheld or stand mixer fitted with a paddle attachment, beat the butter on high speed for 2-3 minutes or until lightened in color and creamy.
Add the peanut butter, powdered sugar, heavy cream, and vanilla. Turn the mixer on low speed so the powdered sugar doesn't splatter everywhere, then once combined raise it to high speed and beat for another 3-5 minutes or until fluffy.
Add more powdered sugar as needed to make the frosting more stiff, or more heavy cream to thin it out. Decorate as desired.
Notes
Quickly bring ingredients to room temp: Cut butter into thin slices to make it soften faster. Microwave the cream for 5-10 seconds to take the chill off.
Use creamy commercial-style peanut butter like Jif or Skippy, not crunchy or natural-style peanut butters.
You don't have to sift the powdered sugar unless yours is already clumpy.