Heat transfer when using a grill pan or griddle is by direct conduction. Generally the grill is surmounted by a hot plate or griddle. The sandwich is frequently cooked in a pan or on a griddle. Foods termed "grilled" may actually be prepared on a hot griddle or flat pan. Their shape comes from being restrained in the pan/griddle by a shallow ring. Traditionally, grilled burritos are cooked on a comal (griddle). It is cooked on a large, flat griddle. Sometimes the paste is just cooked over a griddle. Fish was also sometimes grilled on a spit or griddle over a fire. It is baked on a convex metal griddle (a saj) or in a "tannour". Grooved griddle surfaces are a common plate modification for commercial applications. During his execution, the vendor walks through the crowd selling griddle cakes. Cleaning accessories include such items as griddle scrapers and squeegees. Common names include mudfish, mud pike, dogfish, griddle, grinnel, swamp trout and choupique. The finish is aesthetically pleasing, but offers additional benefits to griddle operators.