Before the oven was preheated to 200 degrees, the egg tart was put in and baked.
It's hot, so you can check whether the egg tart skin has gone bad. In addition, repeated thawing of egg tart skin is also easy to be sour. You can sweep a layer of caramel solution on the surface of the baked egg tart, and then put it back in the oven for high temperature baking.
The baking time may not be enough, and the egg tart is not ripe.