1. For the light dough add the flour, baking powder, sugar, and salt to a large bowl and mix until well combined. Add the butter in small pieces, the vanilla extract and the egg and knead until you get a nice smooth dough. Wrap in plastic wrap and place in the fridge for about 30 minutes. For the dark dough do the same but mix the flour with the cocoa powder first. Place that dough also in the fridge for about 30 minutes.

 

2. Preheat the oven to 350°F (180°C). Line several baking sheets with baking parchment and set aside. Take both doughs out of the fridge and shape into 8″ (20cm) long logs. Place those logs next to each other and start braiding/twisting them to connect the two doughs and to get that marble effect. Shape into a ball but do not knead too much. The more you knead that two colors together the finer the marble effect will get but also the darker the dough will turn because the black is quite “dominant” ;) Roll out half of the dough on a floured surface (place the rest in the fridge) and cut out cookies with and without a hole in the center. Look for a nice marble effect for the cookies that have the hole because they will be on top at the end. Place the dough pieces on the baking sheets and bake one sheet at a time for about 10-12 minutes. Take out of the oven and transfer to a cooling rack. Make more cookies out of the leftover dough by collecting leftover dough and rolling it out again. The last cookies will probably be darker than the first ones because you worked the dough much more.

 

3. Add some jam on the cooled cookies without a hole in the middle and press a cookie with a hole in the middle on top to create a sandwich cookie. Let dry and store in tin boxes.