2. The preheating time will be different with different oven sizes. Egg tarts baked in a small oven need to be preheated 12 minutes in advance, and egg tarts baked in a large oven need to be preheated 15- 16 minutes in advance. When the oven is preheated, it needs to be adjusted to 200 degrees. In the process of baking egg tarts in the oven, we should always observe the texture of egg tarts to avoid baking them.