Well I made them, finally and I was right it's a flamin' expensive recipe to get wrong!. My big mistake was not having a large enough pan to cook them in. I'm not sure how deep a brownie is supposed to be but my feeling is not the almost 2" that I ended up with, it meant that I had overcooked edges, but I can confirm that these are seriously, seriously good. I wasn't sure about the coffee, in the raw batter it was very noticeable and I'm not that fond of coffee cake, in the cold cake though it genuinely isn't a noticable flavour. They also keep really well, I wrapped each bit in parchment but I think because they are so much chocolate and so little flour there isn't that much that can dry out, I used pecans rather than walnuts because I prefer the flavour but I will use walnuts next time as I think the added depth is needed here. Anyway I can totally recommend that you make these, they are a doddle to prepare. Melt, stir, chop a bit, fold, bake, a few steps to Brownie Heaven.