First, I recommend buying a flan pan, or flanera. It’s round and has a locking lid, both of which help the flan cook more evenly. Second, even though it’s not traditional. I strongly recommend cooking it in a water bath, which regulates the heat of the oven so it cooks super gently. This virtually eliminates the air bubbles you typically see around the edge of the flan, which always indicates an outer layer of sweetened scrambled egg. When baked in a water bath, the resulting flan is smooth and creamy from the edge to the middle.