I have a cupcake recipe that calls for buttermilk, but I don't have any- just regular milk. Is there a substitution?
Add about a tablespoon of lemon juice to every cup of milk.
Yes, you can use stirred sour cream or yogurt (thin with a little milk.) OR for each cup of milk, you can add 1 TBSP of plain vinegar or 2 TBSP lemon juice to it, let sit 5 minutes and dont worry if it looks curdled.