Buttermilk

Buttermilk is kind of like milk, but tastes a bit more sour. It's made when people churn (mix really hard) cream to make butter. After they get the butter, there's still some liquid left over in the churn that's kind of like milk but a bit thicker. That's the buttermilk! People used to use it a lot for baking and cooking because it makes things fluffy and tender. Nowadays, some people also like to drink it or use it in smoothies because it's low in fat and has some vitamins and probiotics (good bacteria for your tummy).