Funfetti Whoopie Pies Ingredients Cookies: 2 sticks softened butter 1 1/4 cup sugar 2 teaspoons vanilla 1 teaspoon imitation butter flavor 1 egg 2 cups cake flour 2/3 all-purpose flour 3/4 teaspoon baking soda 1/2 teaspoon salt 1/2 cup colored sprinkles More sprinkles for rolling Filling: 1/2 cup heavy cream 1 teaspoon vanilla 2