These little cases are so-called because of their size - bouchée means mouthful.
Bake on dampened baking sheets at 220°C, 20-25 minutes. To ensure straight rising, put a metal cutter at all four corners of the sheet and place another sheet on top. As bouchées rise, the top sheet prevents them toppling over.
Roll out two 3-mm thick sheets of dough. Lay one on top of the other; brush with egg wash.
Chill or freeze pastry, then cut through both layers of dough with a 7.5-cm fluted pastry cutter.
Cut out the centres in the top layer of dough with an oiled 3.5-cm plain cutter.