The grilled cheese (sometimes known as a toasted sandwich or cheese toastie) is a hot cheese sandwich typically prepared by heating slices of cheese between slices of bread with a cooking fat such as butter or mayonnaise on a frying pan, griddle, or sandwich toaster, until the bread browns and the cheese melts.

The cheese dream, an open-faced grilled cheese sandwich, became popular in the U.S. during the Great Depression.^[1] U.S. government cookbooks describe Navy cooks broiling "American cheese filling sandwiches" during World War II.^[2]

A grilled cheese sandwich is made by placing a cheese filling, often cheddar or American cheese, between two slices of bread, which is then heated until the bread browns and the cheese melts. A layer of butter or mayonnaise may be added to the outside of the bread for additional flavor and texture. Alternatives may include additional ingredients, such as meat, peppers, tomatoes, or onions.^[3]

A grilled cheese may also be made in a sandwich toaster, particularly in the United Kingdom where the dish is normally called a toasted cheese sandwich or cheese toastie.^[4]

Some restaurants, food carts and food trucks in the United States specialize in the grilled cheese sandwich. The Grilled Cheese Grill restaurants were a combination of reclaimed vehicle and food cart restaurants that focused on gourmet grilled cheese sandwiches in Portland, Oregon.^[5] The Grilled Cheese Truck is an American food truck company serving gourmet "chef driven" grilled cheese sandwiches.^[6]

Microwavable frozen toasted sandwiches are available in supermarkets in a variety of locations. One example is the McCain Micro Toastie, which was launched in supermarkets in the UK in 2002.^[7]