The Best Buttermilk Substitutes: Milk and Lemon or Vinegar
In a 1-cup measuring cup, add 1 Tablespoon of fresh lemon juice. Top the lemon juice with skim, low fat or whole milk. Stir and let sit for two minutes. After two minutes, your milk is both acidic and curdled. If you need 2 cups of buttermilk, add 1 tablespoon plus 1 teaspoon of lemon juice or vinegar to the milk. Two tablespoons aren’t necessary.