Why does a sweet bread collapse in the middle?

1. Too much baking powder or yeast: Excessive leavening agents can cause the bread to rise too quickly, leading to a collapse.

2. Not enough liquid: If the dough is too dry, it won't have enough moisture to form a stable structure, causing it to collapse.

3. Too much sugar: Sugar absorbs moisture, so if there's too much of it in the dough, it can interfere with the formation of gluten, resulting in a weaker structure and potential collapse.

4. Oven temperature too high: If the oven is too hot, the crust of the bread can set too quickly, preventing the bread from rising properly and leading to a collapse.

5. Opening the oven too early: Opening the oven door before the bread is fully baked can cause the temperature to drop, leading to a loss of volume and potential collapse.