What is "rusk"?

Rusk is a hard, dry biscuit or bread that is often used as a teething food for babies or as a crunchy snack for adults. To make rusk, bread is baked until it is completely dry and crisp, and then sliced into small pieces. The slices are then baked again until they are completely dry and hard. Rusk can be made from a variety of breads, including white bread, whole wheat bread, and rye bread, and can be flavored with spices, herbs, or sweeteners. In addition to being used as a teething food or snack, rusk can also be used as a topping for salads or as a crunchy ingredient in recipes like meatballs or stuffing. Rusk has a long shelf life and can be stored in an airtight container for several weeks.