Chocolate Chip Whoopie Pie with Buttercream or Marshmallow Fluff Filling

2 c. brown sugar

1 1/2 sticks butter, softened

3 eggs

1 t. vanilla

3 1/2 c. SR flour

1 c. milk

2-2 1/2 c. chocolate chips

*Buttercream Filling:

2 1/2 sticks butter, softened

3 1/2 c. powdered sugar

1/2 t. salt

1 t. vanilla

3 T. heavy cream

Preheat oven to 350. Cream butter and sugar until smooth and creamy. Add eggs and vanilla. Add flour, alternating with milk until well combined. Stir in chocolate chips. Scoop dough, using small cookie scoop, onto parchment paper lined baking sheet. Bake 10-12 minutes until edges are lightly browned. Cool. Make the filling by beating softened butter until creamy and smooth. Add powdered sugar, salt, and vanilla. Mix well. Add heavy cream. Beat on high speed at least 3 minutes until light and fluffy. Pipe or scoop 1 T. filling onto 1 side of cooled cookie. Top with additional cookie.  Repeat with remaining cookies. Individually wrap whoopie pies in plastic wrap. Store in airtight container at room temperature or place in freezer to keep longer or eat frozen. 

*These can also be made with marshmallow fluff filling instead if you prefer. 

1 stick butter, softened

1 c. powdered sugar

1/2 jar marshmallow fluff

1 t. vanilla

Place all ingredients in bowl and beat at medium speed until light and fluffy. 

**Top pies with ganache if desired:

2 2/3 c. milk chocolate chips

1 c. heavy cream

1 stick butter

Heat cream and butter. Stir. Place chips in bowl. Pour hot cream mixture over chips and let set for 5 minutes. Stir. Let set another 20 minutes before spooning over whoopie pies. Place in refrigerator to set. The ganache makes these whoopie pies very rich, but oh so yummy!