Preheat oven to 350 and spray baking sheet with cooking spray.
Combine flour, salt, cocoa and baking soda in a mixing bowl.
1 1/3 cup flour, 1 tsp salt, 1/2 cup cocoa powder, 1 tsp baking soda
In a separate bowl, mix brown sugar, sugar, butter, milk, vanilla, peanut butter & egg.
1 cup brown sugar, 1/4 cup sugar, 1/2 cup butter, 1 tbsp milk, 1 tbsp vanilla, 1/3 cup peanut butter, 1 egg
Slowly mix the dry ingredients into the wet ingredients.
Set aside a few Reese's Pieces and add the rest to the mix.
Scoop tablespoon sized balls of dough , spacing evenly across the baking sheet. Flatten each ball slightly with a spoon.
Bake 12-15 minutes, then remove cookies from the oven and cool on a cooling rack.
Once cookies are cool, spread frosting on six of the cookies, then top each with another cookie.
8 ounces Vanilla frosting
Push Reese's Pieces and/or mini Reese's Peanut Butter Cups into the frosting.
Reese's pieces, Reese's Mini Peanut Butter Cups
Enjoy!