Which cooking technique involves heating items gradually from the surface to the center?

Baking is the correct answer because this cooking technique exposes food to dry heat in an enclosed space, typically an oven. The process involves gradually heating the items, allowing the heat to penetrate from the outer surface toward the center. This method is particularly effective for items like bread, pastries, and casseroles, which need time for the heat to evenly distribute throughout the dish. The gradual heating promotes even cooking and helps achieve the desired texture and flavor.

In contrast, broiling uses direct, high heat from above the food, which can cook the surface quickly without allowing sufficient time for heat to penetrate deeply. Grilling involves cooking food over direct, high heat from below, leading to a quick sear on the outside without a gradual heating effect. Roasting, while similar to baking, often involves higher temperatures and is typically used for larger cuts of meat or vegetables, where the outer layer cooks rapidly, potentially resulting in uneven cooking unless carefully monitored.