How can I make buttermilk with ingredients in my home?

Making a buttermilk substitution is easy. Pour a tablespoon of vinegar into a glass measuring cup. Add enough milk to make 1 cup. Let the mixture sit a few minutes and stir. You could also mix in a spoonful of plain yogurt or sour cream if you have either on hand. For more last minute help, keep this emergency substitutions guide handy.