1 tsp baking powder
a pinch of salt
1 tsp vanilla sugar or vanilla extract
5.3 oz. cold butter, cubed
6.1 oz. sweetened condensed milk
2-3 Tbsp water
a small egg whisked with some water, for brushing
Mix the dry ingredients (flour, baking powder, salt, vanilla sugar) in a bowl, then add the cold cubed butter. Using a knife, cut the butter into the flour mixture, until it resembled wet crumbs. Now add the condensed milk and using your hands, knead into a ball (you may not need the water at all). Place the dough into the fridge for half an hour, so the gluten can relax a little. On a lightly floured surface, roll out the dough until 3-4 mm thick (1/8th of an inch). Cut into shapes (I cut into diamonds, using a roller cutter). Transfer the cookies into a lined baking sheet and brush with an egg wash. Bake in a preheated 200 C / 400 F oven until light golden brown.