Mille Feuille (Napoleon Pastry Sheets)
Use 3 small rectangles of the pastry to make each Napoleon.
Chef John's Vanilla Bean Pastry Cream is delicious piped between layers of Napoleon pastry.
To make the icing, simply add enough water or milk to powdered sugar, until the right consistency is reached. For the chocolate one, I started with one part unsweetened cocoa to four parts powdered sugar, and then stirred in the liquid.