Step 1

For the cookies:

Step 2

Position oven racks in the upper and lower thirds of the oven, preheat oven to 375 degrees. Line two cookie sheets with Silpat liners or parchment paper.

Step 3

In a mixing bowl whisk together flour, cocoa powder, baking soda, baking powder and salt to combine. In the bowl of an electric stand mixer fitted with the paddle attachment beat together butter and sugar until pale and fluffy. Mix in egg and food coloring. With mixer set on low speed add dry ingredients and mix until combined.

Step 4

Shape the dough into balls, about 1 slightly heaping tablespoon each, and place the dough balls 3-inches apart on prepared baking sheets. Using your fingers lying flat (or the bottom of a drinking glass if it's not too sticky for you), evenly flatten the dough balls slightly. Bake until edges start setting, about 7 - 8 minutes. Cool on baking sheet several minutes then transfer to a wire rack to cool completely.

Step 5

To make the filling:

Step 6

In the bowl of an electric stand mixer fitted with the paddle attachment, beat together powdered sugar, shortening, butter, water and vanilla until light and fluffy.

Step 7

Place the filling in a pastry bag fitted with 1/2-inch round tip. Turn half of the cookies over with bottoms facing upright and pipe about 1 Tbsp of the filling over cookies. Place remaining 1/2 of cookies over frosted cookies to sandwich cookies together. Store in an airtight container.