I'm about to start baking a Lemon Blueberry cake (decorated like a baseball) that calls for buttermilk.  I didn't buy buttermilk because I have a LOT of whole milk that I could sour.  After reading the buttermilk cake post I'm rethinking that idea. Emulsifiers?  So...

1.  Should I go buy buttermilk?

     or

2.  Sour the whole milk with lemon juice or vinegar - and if so-

3.  Which is better?  Lemon juice or vinegar?  I have both.

i like to use apple cider vinegar but lemon would work with your lemon menu -- if you can get real buttermilk that would make a better cake but often the 'buttermilk' we get now is just cultured milk -- real buttermilk is a by product of separating cream from milk -- it used to have real yellow butter flecks in it -- the cultured buttermilk we get now is milk with a culture added to sour it -- there's a difference -- so real buttermilk is better but the others all work

powered sacco buttermilk is real buttermilk

I now keep Sacco powdered buttermilk at home because I make the Sky High buttermilk cake a lot. I also keep it because Cooks Illustrated said it would successfully substitute the liquid one. We love buttermilk pancakes too, so we're glad we can use the powder and have it always available. We made pancakes with the powder once when we didn't have the liquid buttermilk, and they were fluffier!

I will definitely pick up some powdered bmilk to have on hand.  The cakes look and smell amazing!  It's a new recipe and I'm trying to figure out how to sneak a taste.  They came out of the pans perfectly and completely level.  Not even any crumbs to pick! 

lol 4laynes. Maybe you can take an apple corer and take a perfectly cut round little piece out? Or when you torte it, slice a very thin piece for you?