After many years enjoying raw milk, I can’t believe I just discovered this. If you leave unpasteurized milk on the counter for a few days, it will curdle into a yogurt-like consistency, a little sour but not unpleasant. It’s called clabbered milk, and for nearly the entire existence of milk-drinking humanity, it was the main leavening agent for quick breads like biscuits and corn bread. It is unbelievably easy to make: you simply leave the milk (covered) on the counter for a few days at room temperature. Apparently you can speed the process by adding a touch of another fermented product, like yogurt or kefir, but it’s not necessary.