Pastry can be savory or sweet and is made from a dough of flour, water, and shortening. Shortcrust pastry is the simplest and most common type, used mainly in tarts and quiches. It is made with flour, fat, butter, salt, and water and results in a short, tender crust when the fat coats the flour strands. Flaky pastry has many thin layers that create a crisp, buttery texture when baked. Puff pastry has numerous layers that cause it to rise up in the oven from water and fats expanding into steam. Choux pastry is a light dough that is often piped into shapes and filled with cream after baking.