Milk + Lemon Juice (Best Option)
1 cup milk + 1 tablespoon lemon juice (let sit 5 minutes)This substitute works because the acid from lemon juice curdles the milk slightly, mimicking the acidity and tang of buttermilk which is important for balancing the chili’s spices and tenderizing meat proteins.
For best results, use whole or 2% milk and allow the mixture to sit for at least 5 minutes to develop the proper acidity and slight thickness. Stir before adding to the chili.
Compared to buttermilk, this substitute offers very similar flavor and acidity, maintaining the chili’s intended complexity and texture.