Apple crisp dessert conjures up all sorts of memories.You might remember being enticed by its distinct aroma -- cinnamon and nutmeg -- when your Mom baked it. It's easy to make and gives you the warm flavors of apple pie without the hassle of making a crust; the treat's topped with a layer of oatmeal streusel that gives it an added layer of flavor and a crispy texture.

Oats come from oat groats, which are the kernels harvested from grass-like plants. Oat groats are steamed and rolled into flakes to produce rolled oats. The process stabilizes the beneficial oils in rolled oats and helps them stay fresher for longer; it also lessens the cooking time. Quick oats are made from more thinly rolled flakes. Longer steaming helps them cook even faster than rolled oats. They have the same nutrients as rolled oats but a smoother texture.

The topping on apple crisp typically includes either brown or white sugar, flour, butter, cinnamon, nutmeg and oats. Most of the flavor comes from the sugar and spices, while the butter, flour and oatmeal act as binders to make the mixture crumbly. Either rolled oats, also called old-fashioned oats, or quick or quick-cooking oats are appropriate for the recipe. Baking times are not affected by the type of oats used. Rolled oats produce a chewier topping than quick oats but the flavor is almost identical. Avoid instant oats or steel cut oatmeal in apple crisp toppings. Instant oats are precooked and disintegrate when baked, and steel cut oats are unrolled, so they don't bake well and impart a raw oat taste.

Although oats are traditionally included in apple crisp toppings, other ingredients taste just as good. Add chopped nuts such as almonds, walnuts or pecans to the streusel recipe or cook raisins until soft and add them to the topping mixture. Crushed butter or shortbread cookies add extra richness to apple crisp toppings.

For a softer texture in apple crisp, slice the apples thinly. If you prefer a chunkier texture, cube the apples instead of slicing them. Apple crisps can be made ahead of time, refrigerated and reheated in the oven or microwave before serving. Ice cream and whipped cream make tasty apple crisp toppings. For family-size apple crisp dessert, bake it in a 9-by-9-inch square pan. If you're feeding a crowd, double the recipe and bake it in a 13-by-9-inch baking pan and adjust the cooking time accordingly.