What type of appliance consists of a flat metal surface for cooking food with a grease trough?

A griddle is a cooking appliance that features a flat metal surface specifically designed for cooking food. This surface allows for even heating and is ideal for a variety of foods such as pancakes, burgers, and eggs. The inclusion of a grease trough serves a practical purpose by collecting excess grease and liquid, which helps in maintaining a cleaner cooking area and prevents flare-ups. This design enhances both safety and efficiency while cooking.

In contrast, a fryer typically involves submerging food in hot oil, lacking a flat surface or grease trough. A stovetop refers to a cooking surface featuring various burners, which does not have the single, flat surface characteristic of a griddle. A convection oven, while a cooking appliance, operates through circulating hot air and does not possess a flat cooking surface like a griddle. This distinction underscores why a griddle is the most accurate answer to the question regarding the type of appliance described.