Which cooking method involves submerging food in hot oil?

Deep-frying is a cooking method that involves submerging food completely in hot oil. This technique allows for a rapid cooking process, resulting in a crispy, golden-brown exterior while effectively cooking the inside of the food. The high temperature of the oil creates a barrier that seals moisture inside the food, leading to a juicy interior. Additionally, deep-frying can be used for a wide variety of foods, enhancing flavors and textures due to the oil's ability to conduct heat evenly.

In contrast, steaming uses water vapor to cook food, which does not involve submersion in oil. Poaching involves cooking food gently in simmering water or broth, while sautéing refers to cooking food quickly in a small amount of oil or fat over high heat, typically in a skillet, not submerging it like in deep-frying. This makes deep-frying distinct among cooking methods, as it is the only one that specifically requires complete immersion in hot oil.