The ideal cooking time for oven-baked sweet potatoes is approximately 45 to 60 minutes. This duration allows the potatoes to become tender and caramelized on the outside while maintaining a soft, sweet interior. The specific cooking time can vary depending on the size and thickness of the potatoes, as larger or thicker ones will require more time to cook thoroughly.

The reason for this range in cooking time lies in the heat distribution and the need for even cooking. When baking sweet potatoes in an oven, the heat circulates around the potatoes, causing them to cook from the outside in. Larger or thicker potatoes have more mass and require more heat to reach the same internal temperature as smaller or thinner ones. According to the United States Department of Agriculture (USDA), sweet potatoes should be cooked until they are tender when pierced with a fork or knife. This typically takes around 45 to 60 minutes at a preheated oven temperature of 375°F (190°C).

Research conducted by the University of Georgia's College of Agricultural and Environmental Sciences suggests that the cooking time can also be influenced by the oven's efficiency and the initial temperature of the potatoes. For instance, if the oven is not preheated properly, it may take longer for the sweet potatoes to reach the desired tenderness. Additionally, if the potatoes are room temperature when placed in the oven, they will cook faster than if they are cold. This is because cold potatoes require more heat to bring them up to the oven's temperature before they can begin to cook.

In summary, the recommended cooking time for oven-baked sweet potatoes is 45 to 60 minutes, depending on the size and thickness of the potatoes, as well as the oven's efficiency and the initial temperature of the potatoes. Ensuring that the oven is preheated and that the potatoes are at room temperature before cooking can help achieve the best results.