So I made cultured butter and, in addition to almost 400g of butter I got about 6 dl of tangy, lecithin-y buttermilk goodness.

Alas, buttermilk doesn't feature in Swedish cooking and baking.

So, I ask you, the American people:

What can/should I cook or bake with buttermilk? I'm looking for things that make excellent use of this strange ingredient. Things that can't be made properly without it. Things that taste great because of it. Things that can display its tangy emulsifying powers.