I don’t have a huge variety to choose from here in Charlotte, NC, but I’ve been really happy with my results using Green and Black’s unsweetened cocoa powder.
As far as unsweetened chocolate goes, I have one choic: Ghiradelli (spelled wrong, I’m sure).
If it’s anything other than unsweetened, I like to mix chocolates, as I’ve found I prefer that to using a single chocolate. So, if I want a 70% chocolate, I’ll use, say, 1/3 weight of each of a 70%, 85% and 55% bars (or thereabouts), often mixing brands. I really like the chocolate used in the Endangered Species chocolate bars, on the whole, and also the Divine chocolate bars, and I tend to use them quite a bit.
For white chocolate, I found that I preferred Lindt over Green and Blacks (blind taste test) and so did the hub, and that surprised me! I’d like to find something I like a little better than Lindt, even, though.
Anne, where have you been able to find Green and Black’s cocoa powder in Charlotte? I have been able to find the bars but no luck on the cocoa powder.