1 Mix both types of flour and baking powder in a bowl. Cream butter until smooth in a mixing bowl with the whisk attachments of a hand mixer at medium speed. Add sugar, vanilla sugar, 2 tablespoons milk, salt, cardamom, cinnamon and cloves. Grate in about ½ teaspoon nutmeg and mix quickly to combine.
2 Mix in 1 egg. Add the flour and baking powder all at once and mix until crumbly.
3 Working quickly, knead with your hands into a smooth dough and shape into a ball. Flatten into a disc and wrap in plastic wrap. Place in the refrigerator for at least 1 hour.
4 Coarsely chop pistachios. Separate the remaining egg. Whisk the egg yolk in a cup with the remaining milk (save white for another use).
5 Roll out the dough 4-5 mm (approximately 1/4-inch) thick on a floured work surface. Cut dough with a 3–4 cm (approximately 1 1/2-inch) round cookie cutter. Knead the scraps, roll out again, and cut out remaining dough.
6 Line 2 baking sheets with parchment paper and place cookies on sheets. Brush with beaten egg yolk and sprinkle with the pistachios.
7 Bake in preheated oven at 200°C (fan oven 180°C, gas mark 3) (approximately 400°F/convection 375°F) until golden brown, about 12 minutes. Cool on a wire rack before serving.