I love brownies and I love buttermilk, so I thought I'd try and combine the two. Also I am hungry and wanting brownies and no cafes are open past 8:00 PM in this nutty little town.
Anyways, here's the first take:
OK go go go MELT the BUTTER in a pot over medium-low heat. When melted, add the COCOA POWDER, mix well, remove from heat. Add SUGAR, mix, add COFFEE and BUTTERMILK, mix, add EGG (sans shell), mix just until combined. That reads a bit like one of those old-style text based adventure games, doesn't it? Weird. Combine the flour and baking powder in a big ol' bowl, add wet ingredients plus chocolate chips, mix just until combined (but do make sure you haven't left any flour clumps in there, those are unpleasant.
Portion batter into a greased muffin tin, bake at 350ºF for fifteen minutes or until a toothpick comes out clean when stuck in the middle of the biggest of those suckers.
You could go ahead and use a brownie pan or something, but then you've got to cut them and things, whereas a muffin tin gives you delicious, good-to-go little servings.
Post-analysis: These are a little cakey. There must have been too much fluid in the batter, and there wasn't enough chocolateyness too them. Taste pretty nice, but they are not what I was going for.
Not terribly sweet, which I like (and mom likes, apparently), and you can't really pick up on the buttermilk flavour too much. I think the simplest thing might just be to stick with cream-cheese if I want to the cultured dairy flavour in brownies, because buttermilk brings too much fluid to the stage.
I may try a brownie recipe with strained yogurt later.