2 cups unsifted flour
1/3 cup unsweetened cocoa powder
1 teaspoon baking soda
1/4 teaspoon salt
3/4 cup milk
1 teaspoon vanilla extract
1 egg
1/3 cup vegetable oil
1 cup granulated sugar

Preheat oven to 350 degrees F.

Combine flour, cocoa, baking soda and salt in bowl; set aside.

Combine milk and vanilla extract in measuring cup; set aside. Beat egg and oil in bowl of electric mixer until combined.

Add sugar to egg-oil mixture; beat until pale yellow, about 3 minutes. Add flour and milk mixtures alternately to egg mixture, beginning and ending with flour mixture.

Drop about 1 tablespoon of the batter onto greased cookie sheets, 2 inches apart. Bake until top springs back lightly when touched, 5 to 7 minutes. Remove to wire racks to cool.

Filling
2 cups Marshmallow Creme
1 cup confectioners' sugar
1/2 cup (1 stick) unsalted butter, softened
1 teaspoon vanilla extract

Combine Marshmallow Creme, confectioners' sugar, butter and vanilla in bowl of electric mixer. Beat on medium speed until fluffy, about 2 minutes. Spread filling between 2 cake halves to make sandwich.

Yields 15 pies.