But I Don't Have Buttermilk...

I don't always plan ahead when I'm going to bake.  Sometimes, I just decide on the spur of the moment that I need some baking therapy.  That being said, I occasionally run into ingredients that I don't have on hand.  This very thing happened the other day with buttermilk.  When a recipe calls for buttermilk, you can't just substitute regular milk.  That will throw off the chemistry, and it won't bake up the way it's supposed to.  Fortunately, buttermilk is pretty easy to substitute for.  See, it's the acid in buttermilk that you need.  The acid reacts with the baking powder and makes lots of little bubbles, which make your baked goods rise.  Where else can you find acid?  Well, lots of places really. 

Substitution #1:

For each cup of buttermilk you need, measure out one tablespoon of vinegar or lemon juice, and then fill the rest of the way up to the 1 cup line with regular milk.  Allow that to sit for 5 minutes, and you have buttermilk... basically. 

Substitution  #2:

Using sour cream or plain yogurt, mix equal portions with regular milk to make whatever measurement you need.  So if you need 1 cup, mix together 1/2 cup of sour cream with 1/2 cup milk.  Whisk them to make sure there are no lumps, and you're good to go.