Buttermilk is a tangy, slightly thick dairy drink that tastes nothing like butter, despite its name. Originally, buttermilk was the liquid left behind after churning cream into butter: thin, sour, and surprisingly refreshing. Today, most buttermilk is made by adding special bacteria to regular milk, which gives it that characteristic sour taste and thicker texture.

Buttermilk works magic in baking. When you mix it with baking soda in pancake or biscuit batter, a chemical reaction occurs that creates tiny bubbles of carbon dioxide, making your pancakes fluffy and your biscuits rise beautifully. This same tangy quality makes buttermilk perfect for marinating chicken before frying, since the acid helps tenderize the meat while adding flavor.

You’ll rarely see people drinking buttermilk straight from a glass anymore, though some folks still enjoy it that way. Instead, it’s become a baker’s secret weapon. When a recipe calls for buttermilk and you don’t have any, you can make a quick substitute by adding a tablespoon of lemon juice or vinegar to regular milk and letting it sit for five minutes.