Clabber
Before you get scared off by the name (or the description for that matter), consider that yogurt is just fermented milk. We tend to be adverse to the concept of sour milk, but it’s actually used for plenty of delicious foods. One of those foods was clabber, which was very popular in colonial times.
Before you toss your sour milk next time, check out some recipes for clabber. Colonists used to season it with nutmeg, cinnamon, or pepper.