Although many of us would consider almonds to be nuts, scientifically speaking they are closer to peach pits. They are actually the fruits of deciduous (meaning that the leaves fall off every year) trees originally found in Asia and North Africa. Instead of growing a sweet fleshy pulp around the seed, almonds develop a leathery coating. Beneath this shell lies a hardened pit with a dark skin, much like a pit from a freestone peach.
Almonds come in two varieties, sweet and bitter. Sweet almonds are used in many Asian dishes, as well as dessert pastes and garnishes. A popular use for crushed sweet almonds is a European candy base called marzipan. They are mixed with glucose and water to form a thick but pliable paste. Marzipan can be molded into cookies or other identifiable shapes by skilled dessert makers.
Sweet almonds can also be processed into essential oils or extracts. The extract is commonly used as an alternative to vanilla extract in diabetic-safe recipes. The sweet type are often roasted and turned into slivers or chunks for texture in ice creams or puddings.
The bitter form is also used in cooking, but it must first be processed in the raw stage. Bitter almonds contain a toxic amount of prussic acid, which can be further refined into a poison called cyanide. Consuming a handful of unprocessed, raw ones can lead to death from this poison. Consequently, the prussic acid must be leached out before they can be used by humans as food.
The designation "bitter almond" does not necessarily mean a disagreeable bitterness. Extracts from them are used to flavor a very flavorful liqueur called amaretto. The slight bitterness is a distinctive characteristic of amaretto, which is often mixed with orange juice or other sweet mixer to balance it out. They are also processed into slivers and whole pieces for salads and casseroles.
Almond trees can be found in Asia, Europe, North America and Africa. In the United States, virtually all those for commercial sale are produced in California. Grocery stores may carry raw ones for cooking, roasted ones for snacking, ground ones for pastes and chopped almonds for garnishes and salads. They are very high in the good form of cholesterol, and are often treated with hickory-smoked salts or other savory flavors.