Custard pastry is a type of dessert that consists of two layers of pastry, usually puff pastry, filled with a custard-based filling. The most popular custard pastry is the NAPOLEON, which is made with eight layers of puff pastry and a custard filling. FLAN is another type of custard pastry, which is made with four layers of puff pastry and a custard filling. Both the NAPOLEON and the FLAN are popular desserts that are enjoyed around the world.