A frittata is an Italian egg-based dish similar to an omelet. It is made by combining beaten eggs with other ingredients such as vegetables, cheese, and meats, and then cooked in a skillet. The difference between a frittata and an omelet is that a frittata is not folded over like an omelet, but instead is cooked until the top is set. Frittatas are often served as a main course or as a side dish.