On reheating soups.
If you've ever made soup or sauces and stored the leftovers in the refrigerator, you know they thicken as they sit. But be careful when you reheat it. On the one hand, you don't want it to scorch from being too thick. On the other hand, you don't want to overestimate how thick it is. Let it begin to warm up before you add liquid (water, cream, milk, etc.) When it is just starting to get warm, you will be better able to judge its consistency.