If served as a main meal or a container for appetizer dips, round loaves of bread are commonly used to contain heavy stews, creamed foods, or dips to be spread on crackers and other snacks. When served as small appetizers, the shells are smaller in size and filled with chopped, rolled or melted ingredients that could include fish, shellfish, meat, poultry, mushrooms, cheese, caviar, eggs, salsas, savory fillings, or vegetables. Typical dessert croustades are also smaller in size and filled with stuffings that may include sorbet, ice cream, pudding, pie fillings, or any similar sweet fillings.
The shells for croustades can be purchased in food stores as pre-made crusts or they can be made with bread or cake, depending on the intended use. With bread or cake, the texture should be firmed by either toasting, drying or baking the formed shell into a golden brown crust. If a loaf of bread is used, the baked and crusty texture works well to be hollowed out and filled with ingredients. For appetizers or desserts, sliced bread and cake are used, cutting the slices into small squares or rounds. In the center of the cut slice, a rounded area is pressed with a thumb or spoon to create an mold that holds the filling. Another method for preparing shells for croustades is to use a rolling pin to flatten slices of bread or cake, making the slice thin and pliable. After being rolled into thin slices, the bread or cake is often brushed with butter or oil on both sides and then formed into a shell shape by placing the slice into a shaped baking tin. After placing it in a tin, the shells are baked for 15 to 20 minutes to create a crispy browned shell for filling. A variety of shapes can be made that range from deep and wide shells to small platter-shaped shells that simply hold a very small amount of ingredients.