I have a recipe that calls for buttermilk .. I have none and don't want to make a trip into town .. I googled it and several sites say to add a tablespoon to regular milk and let it sit out for 5-10 minutes until it looks curdled .. .... does this sound right?

Making a recipe that calls for buttermilk? Use this simple substitute, and you won't need to buy any:
Prep Time: 5 minutes
Total Time: 5 minutes
Ingredients:

Milk (just under one cup)
1 Tablespoon white vinegar or lemon juice

Preparation:

1. Place a Tablespoon of white vinegar or lemon juice in a liquid measuring cup.

2. Add enough milk to bring the liquid up to the one-cup line.

3. Let stand for five minute. Then, use as much as your recipe calls for.

All adding vinegar to milk does is add acid. No flavor and no emulsifiers, which is the whole reason to use buttermilk in the first place.

My suggestion is to use either sour cream or yogurt 1 for 1 if you don't have buttermilk on hand.

Fromscratch, what do you think about the dried buttermilk product?

I've never used it - I priced a can once, $12 and it essentially made a whole gallon of buttermilk. Fresh is only $4/gallon for me! And I go thru a ton of it.

I use the the canned buttermilk and I love it...it has a longer shelf life for me. I don't use it that often so it works.