I do it about every third time I make homemade yogurt. I get impatient, turn the stove burner up too high, and burn a nice layer of black milk on the bottom of the pot. Luckily it’s an easy fix. Just put a bit of water and baking soda in the pot, place it back on the stove and boil it. The burnt milk lifts off in specs, or you can hasten the process by scrubbing a bit with a wooden spoon. When the pot cools, you can wash the pot with soap and water as usual.