奶奶用酪乳做了松软的小饼干。

Grandma used ___buttermilk to make fluffy cookies.

早餐时，我喜欢用酪乳和水果做一杯奶昔。

For breakfast, I like to make a smoothie with ___buttermilk and fruits.

她用酪乳腌制牛排，让肉质更嫩。

She marinated the steak in ___buttermilk to make it more tender.