Made some King Arthur GF Chocolate Cupcakes, then filled and topped them with this Fluffy Peanut Butter frosting recipe that I found on AllRecipes.com
1/2 cup butter, softened
1 cup creamy peanut butter
2 cups confectioners sugar
3 tablespoons milk, as needed
Note: I doubled the recipe and used about 3.5 cups of sugar, and no milk.