Add the butter into a bowl and then sieve in the powdered sugar. It is important to sieve the sugar to avoid lumps in the dough later. Add the lemon zest, vanilla extract, and egg.
In a separate bowl, combine the flour, baking powder and salt. Sieve into the mixture. Knead the dough until everything is combined.
3 ½ cups all-purpose flour, 1 teaspoons baking powder, 1 pinch salt
Half the dough. Add the cocoa to one-half and knead until it is mixed in well.
1 tablespoon cocoa powder
The dough will have become very soft from all the kneading, so wrap it in cling film and place in the fridge for 1-2 hours to cool down.
Prepare the egg wash to create the cookie patterns.
1 egg
Black and White Half Circle Cookies
Divide the dough into two equal-sized rolls, one with the white dough and one with the black dough.
Using a sharp knife, slice the roll lengthwise in half. Brush the cut side with egg wash and combine the black and the white sides into a single roll. Place onto a tray to chill in the fridge for later.
Black and White Fraction Circles Cookies
Using the black and white dough, form two equal-sized rolls.
With a sharp knife, slice the roll lengthwise in half, and slice the half again so you get two white quarter circles and two black ones. Brush the cut side with egg wash. Now, create two big rolls by attaching the black and white fraction pieces together. Place the rolls on a tray to chill for later.
Spiral Cookies
To make the spiral pattern, roll out two squares of the black and white dough. Brush the surface of one of the doughs in egg wash, then carefully layer the second dough on top of the other. Using a sharp knife, slice the edges to create an even rectangle. Roll up the edges to create one large roll. Place onto a tray to chill in the fridge until later.
Striped Cookies
To make striped cookies, roll out both doughs to a thickness of approximately 5 mm. Brush the surface of one dough with egg wash and layer the second dough on top. Using a sharp knife, slice the edges to make a square. Slice the dough into three rectangles and place each on another to get a square plank. Place onto a tray to chill later.
Chessboard Pattern Cookies
To create the chessboard pattern cookies, roll out both doughs to a thickness of approximately 5 mm. Brush the surface of one dough with egg wash and layer the second dough on top. With a sharp knife, slice the edges so they make an exact square. Slice the dough into thin strips, and arrange them side by side, alternating colors to create the chess pattern.
Cover your tray with cling film and place the dough in the fridge for about 2 hours to harden.
After the chilling preheat your oven to 200°C / 392°F top to bottom heat. Remove the cling film and line your baking tray with baking parchment.
Place the rolls and planks on a chopping board and, using a sharp knife cut off about2-4 mm thick cookies. Place on the baking trays. Leave enough distance between each cookie, as they will expand during baking.
Bake for 8-10 minutes. The cookies will still be a little soft when you remove them from the oven but will harden when they cool down.
Video
Notes
To create all the patterns, please double the ingredients for the dough. You can adjust the quantities by adjusting the button above where the ingredients are listed. Extra tips- Check out the step-by-step pictures in the main post for guidance. It can also be helpful to watch the short video once, to see how to create the pattern. StorageThey should kept in an airtight container. They last a long time, but to three months so great to make in bulk.