Directions:

1. Heat oven to 375*
2. Combine flour, sugar, cocoa, baking soda, baking powder and salt in a large mixing bowl. Mix with a hand mixer (or a stand mixer, if you're fancier than me) on low until combined.
3. Add butter, one tablespoon at a time. Keep churning with the mixer until it starts to clump together. Add egg and mix until a big blob of sticky chocolate dough forms.
4. Line a cookie sheet with parchment paper. Roll dough in to small balls and place on cookie sheet, about 1.5" apart. (Small like...a gumball. Or a milk dud. And if those references don't conjure an image immediately in your mind, this recipe is probably not for you!)
5. Using moistened fingers, press balls down to form little discs...say, the size of a Nilla wafer. They'll grow a bit when you bake them.
6. Bake for 7-8 minutes. Remove from oven and transfer cookies and parchment to a cooling rack. Repeat until dough is gone.
7. Allow cookies to cool completely.
8. Meanwhile, make the filling. Beat sugar into butter, one tablespoon at a time. Beat in vanilla (and food coloring, if using). Beat for a couple more minutes, until fluffy-looking.
9. Match up pairs of cookies that are the same size. Pipe (much faster and less messy) or smear a layer of frosting and close 'em up. 

Servings: Makes three dozen cookies.

Preparation Time: 45 minutes