Filled sandwiches, also known as 'STUFFED' sandwiches, are a type of sandwich that is filled with various ingredients such as meats, cheeses, vegetables, and sauces. The most popular type of filled sandwich is the gyro, which is a Greek dish consisting of meat cooked on a vertical rotisserie and served in a pita bread with tomatoes, onions, and tzatziki sauce. Gyros are usually made with lamb, beef, or pork, but can also be made with chicken or vegetarian options.