Ulitmate Chocolate Chip Whoopie Pie

Kidsll scream chip, chip, hooray for this yummy take on the classic chocolate chip cookie.

For the cake-cookies:
2 cups all-purpose flour
1 tsp baking soda
¼ tsp salt
¾ cup butter, softened
¼ cup shortening
¾ cup packed brown sugar
½ cup white sugar
1 tsp vanilla
1 egg
2 cups chocolate chunks, chips, broken candy bars, etc. (whatever chocolate you have on hand)
For the filling:
½ cup butter, softened
4 oz cream cheese, softened
2 cups confectioners' sugar
1 tsp vanilla
Sprinkles (optional)

Make the cake-cookies: Preheat oven to 350 degrees.
In a medium bowl, combine the flour, baking soda and salt, set aside.
In a stand mixer (or a mixing bowl with a hand mixer) cream the ¾ cup butter, shortening and sugars until light and fluffy. Beat in the vanilla and egg until fluffy.
Stir in the flour mixture until combined. Stir in the chocolate.
Place tablespoon-size balls on ungreased cookie sheet and bake for 8-10 minutes.
While the cookies are cooling, make the filling: In a stand mixer (or with a hand mixer), beat together the ½ cup butter and cream cheese. Beat in the confectioners' sugar and vanilla.
Place filling in a large, zip-top bag and cut off one corner. Squeeze filling onto flat side of one cooled cake-cookie and top, flat-side down, with another cake-cookie.
Roll edges in sprinkles, if desired.