Fly Me to The Moon Pies

I found this recipe in a scholastic cook book I bought for my kids at their school book fair. These cookies are super yummy and so easy to make. 

Cookies
1/2 cup butter softened
1 cup sugar
1 egg
1 cup evaporated milk
1 teaspoon vanilla
2 cups flour
1/2 teaspoon salt
1/2 cup cocoa powder
1 1/2 teaspoons baking powder

Filling
1 cup butter softened
2 cup powdered sugar
1 teaspoon vanilla
2 cups marshmallow creme

1. Preheat oven to 400 degrees. Lightly grease a cookie sheet.
2. For the cookie crusts: In a large bowl, cream the butter and sugar.Add in the egg, evaporated milk, and vanilla. In another bowl, mix together the flour, salt, cocoa powder, and baking powder. Add flour mixture slowly to sugar mixture while stirring. 
3. Drop the dough onto the greased cookie sheet by rounded tablespoonfuls. Leave at least 3 inches between each one. 
4. Bake for 8 minutes. or until firm when pressed lightly with finger. Allow to cool. 
5. While the cookies are cooling, make the marshmallow filling by blending the butter powdered sugar, vanilla, and marshmallow creme. 
6. Assemble the pies by spreading 2 or more tablespoons filling on the flat side of of the cookie, then cover filling with the flat side of another cookie. Makes about 25 assembled cookies.