Step 1

In a large bowl, cream together 1 cup (225 grams) of softened butter with the white sugar and salt, until light and fluffy.

Step 2

Beat in eggs until fully incorporated.

Step 3

Sieve together the flour, cocoa powder, and baking soda into the mix. Blend well.

Step 4

Add the dry ingredients to the wet ingredients, and mix together until combined.

Step 5

Turn the dough out onto your surface and push together into a flat square. Wrap the dough in plastic wrap and refrigerate for 1 hour.

Step 6

Preheat oven to 325˚F (160˚C).

Step 7

Remove the dough from the fridge, and for ease of rolling out, divide the dough into 4 (this way the dough stays cool longer and prevents the need of re-chilling later on).

Step 8

To roll out the dough, place a quarter of the dough between two sheets of parchment paper (alternatively the dough can be rolled out on a lightly floured surface - though the parchment is preferred as it prevents any additional flour from altering the color/appearance of the dark cookies). Roll the dough between the two sheets of parchment to ¼-inch (½ cm) thickness.

Step 9

Using a small round cookie cutter (alternatively, we found the rim of a champagne glass to be a perfect size!) cut the dough into individual rounds and place on a large parchment-lined baking sheet, leaving at least ½-inch (1¼ cm) between each cookie.

Step 10

Pack together and re-roll out any scraps to cut additional cookies. Repeat with this process with each remaining ¼ of the dough.

Step 11

Bake in a preheated oven for 15 minutes. If baking multiple trays at the same time, be sure to rotate the pans in the oven halfway through. Remove and transfer cookies to a cooling rack to cool completely.

Step 12

To make the filling, combine ½ cup (115 grams) butter, powdered sugar, and vanilla in a medium mixing bowl. Beat together until light and fluffy.

Step 13

Assemble the cookies by spreading a generous scoop of the icing onto one of the cookies and sandwiching it with another. Give it a light squeeze and scrape any excess off to clear and even out the sides.

Step 14

Serve with a glass of milk.

Step 15

Enjoy!