Chocolate Whoopie Pies with Vanilla Filling

It all started with a pan...

My amazing aunt gave it to me for christmas and I hadn't gotten to use it yet. I'm telling you, she may be the only person who can buy me a baking pan that she knows I don't have. She has given me most of the "specialty" pans I own.
Today I finally decided to try it out. I went to Wilton for the recipe, because I figured it would be the safest since the pan is from there, and their recipe was simple.

It is super simple. The batter is quick and bakes up quickly as well. The only issue was that it made twice as many pies as the pan will hold, so I had to wait for them to come out, cool in the pan, etc. before baking more. Oh well, may need to buy another pan! ;)
The filling was really interesting, because it is basically my standard icing recipe but with a jar of marshmallow fluff mixed in. I had actually never tasted that stuff plain, and... Oh my God. It's almost as good as nutella.

I have seen SO many of these on various food blogs (there are even entire cookbooks devoted to them) that I had high expectations. I was not disappointed! The cakes were delicious and fluffy, and the filling was sticky and sweet and like a pillow of sugary goodness. Expect to see some more of these on here in the near future!! Enjoy!

Chocolate Whoopie Pies with Vanilla Filling
(from Wilton)
1/2 cup (1 stick) butter, softened
1 cup firmly packed brown sugar
1 egg
1 teaspoon pure vanilla extract
2 cups all-purpose flour
1/3 cup cocoa powder
1 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon salt
1 cup buttermilk

6 tablespoons butter, softened
1 1/2 cups confectioners' sugar , sifted
1/8 teaspoon salt
1 jar (about 7 ounces) marshmallow creme
1 teaspoon pure vanilla extract

Preheat oven to 350°F. Lightly spray Whoopie Pie Pan with nonstick cooking spray.
In large bowl, beat butter and sugar with electric mixer on medium speed until light and fluffy, about 3 minutes. Add egg and vanilla; beat until well combined.
In another bowl, sift together the flour, cocoa powder, baking powder, baking soda and salt. Add half the dry ingredients into the butter mixture and mix on low speed. When dry ingredients are almost incorporated, stop the mixer and add the buttermilk. Continue to mix on low speed until all ingredients are almost incorporated. Stop the mixer and add the remaining dry ingredients. Mix on low until just combined. Spoon 2 tablespoons of batter into each cavity; spread batter to the edges. Cavity should be about 2/3 full.
Bake for 8-10 minutes or until the top of the cake springs back when touched. Allow cakes to cool in pan 8 minutes. Remove from pan and cool completely before filling.

In large bowl, beat butter with electric mixer until creamy. Add sugar and salt to the butter; mix well. Add marshmallow crème and vanilla; blend well. Use immediately to fill whoopie pies or refrigerate covered up to 1 week. Bring back to room temperature and lightly beat before using.
To assemble, spread on half of the pies and sandwich with the other half.
Makes 12 pies (24 cakes).