Knead the flour, parmesan, chili powder, garlic salt and butter together well, then knead the egg yolks. Form a 20 cm long roll on a floured surface and wrap it in cling film and let it cool for about 30 minutes.
Cut the roll into 0.5 cm thick slices. Halve each slice. Place the cookies 0.5 cm apart on baking sheets lined with baking paper. Sprinkle with chilli powder and garlic salt.
Bake in the preheated oven at 210 ° C for about 20 minutes until they are browned and crispy. Transfer to a wire rack to cool down.