*If you don't have buttermilk, you can mix together ¾ cup milk + ¼ cup plain yogurt + 1 teaspoon lemon juice (or white vinegar) and let sit 5 minutes to thicken. Technically, you only need milk and an acid to make "soured milk," but I recommend adding the yogurt to add body to the mixture so it clings more like cultured buttermilk and coats the bread better.