Whoopie pies are soft chocolate cake cookies sandwiched together with a sweet whipped buttercream frosting. They're a rich, decadent, and nostalgic treat that all ages will enjoy!
Preheat oven to 400 degrees Fahrenheit. Line a baking sheet with parchment paper and set aside.
In a large bowl, add butter and sugar. Using a hand mixer or stand mixer, cream together until light and fluffy, about a minute. Add eggs and vanilla extract. Beat until fluffy, about a minute.
In a separate bowl, sift together dry ingredients: flour, dutch cocoa powder, baking powder, baking soda, and salt.
Add half of the dry ingredients to butter mixture and mix on low until just combined. Add half of milk and mix until combined. Repeat once more to add remaining dry ingredients and milk.
Using a medium cookie scoop, spoon cookie dough 2 inches apart onto prepared baking sheet. Recipe will make 32 individual cookies with a medium scoop.
Bake about 9-10 minutes, or until cookies are puffy and tops have cracked.
Allow to cool for 5 minutes before removing to a wire rack to cool completely.
Buttercream frosting
In a bowl, add room temperature butter and beat until creamy, about 1 minute.
Add confectioner's sugar gradually and mix on low speed until ingredients are fully combined. Then, whip at high speed for 2-3 minutes, or until light and fluffy.
Add vanilla extract and heavy cream, then whip for an additional about 2-3 minutes, or until light and fluffy.
Pipe frosting with a piping bag or spread frosting generously with a knife onto the bottoms of half of the cookies. Top with remaining unfrosted cookies to make sandwiches.
Notes
*It's important that dutch process cocoa powder is used for this recipe, rather than natural cocoa powder. Dutch process gives these cookies their rich color and mild flavor. The leavening agents rely on the proper acidity in this recipe to bake and rise properly.
Cookies will keep for 4-5 days in a sealed container. To help keep cookies fresh, place a slice of bread in the container with the cookies. Replace the bread slice as needed.
Customize your whoopie pies by adding food coloring to the filling or rolling the edges of the frosting in sprinkles.