Cookies with Chocolate Glaze and Pistachios
Mix the butter with the sugar, vanilla sugar, egg, salt and lemon zest until very frothy. Sift the flour with the baking powder, then stir into the dough. Knead together briefly. Wrap in plastic wrap and chill for 2 hours. Roll out on a floured surface 5 mm (approximately 1/4 inch) thick and cut with a pastry wheel in triangles, about 5 cm (approximately 2 inches) in length.
Line a baking sheet with parchment paper. Place the almond halves the cookies and press down gently. Whisk the egg yolk with 1 tablespoon water, then brush onto the cookies. Bake in a preheated oven (200°C or approximately 400°F) on the middle rack until golden, about 10-15 minutes. Allow to cool on a wire rack. Melt the couverture over a hot water bath, then spread on top of the cookies. Sprinkle with pistachios and let dry.