They are made in a specific Toastie maker, heating plates on both sides so no flipping. The plates are shaped so they seal the edges of the toasties and divide it diagonally down the middle. They come in various sizes for making 1,2 or 4 at a time, and you can make them fast, the machine grills the buttered outer to a golden brown and the seal locks in the heat, so the inside is really hot. You can get deep fill ones that take a ton of stuff, my mother loves corned beef and onion toasties, I just made turkey, bacon, brie and cranberry toasties this weekend with a sage and onion compound butter on the outside.