B&W Cookies

Directions

1. 1
   Mix the butter and the sugar until you get a creamy texture.
2. 2
   Add vanilla extract, egg, flour and the lemon zest and mix until it is smooth then split the mixture into 2 even balls.
3. 3
   In one of the balls add cocoa and blend it inches.
4. 4
   Roll both balls until you get a 8 mm thin layer.
5. 5
   Take the egg yolk and mix it with a little bit of water and spread it over one of the layers.
6. 6
   Put the other layer over it and roll them together using a plastic sheet then put the roll in the fridge for about 45-60 minute.
7. 7
   Heat the oven at 180 C.
8. 8
   Take the roll out of the fridge and cut it into thin slices then put them on a tray that has baking paper on it.
9. 9
   Bake them for 15 minutes, let them cool and serve.