I found this recipe on Vegweb for Tofu Sour Cream (which, for the record, came out delicious), involving really simple ingredients: tofu, fresh lemon juice (and it did make a difference using fresh), olive oil, salt. The recipe called for sweetener, but nuts to that. I hate sweetener. Also, vinegar. Meh. Don't really care about vinegar. If I'm adding lemon anyway, I'll stick with lemon, and not have to add another ingredient to keep track of.
However, when reading the comments for the recipe, I wanted to slap my forehead repeatedly. Various folk tried to use /frozen/ tofu.
Clearly, they'd never worked with the stuff before, and weren't aware that when you freeze tofu, it gets a very spongy texture. There are some Chinese dishes that take advantage of this property, and they're lovely (not my thing personally, but I know people who like that extra chewy texture). But when you're blending tofu in a processor or grinder of some sort, you're meant to use the stuff direct from the box.
And I thought /I/ had it hard with writing recipes! For someone who has worked with tofu before, it's very obvious that no amount of grinding is going to get frozen tofu into a soft fluffy cream like you'd get with fresh tofu (the fresher the better, come to think of it). For someone who's never touched the stuff, however, there are bound to be pitfalls. This is why I love VegWeb so much: there's various people who reply to the recipe with their experience, and you can learn from it by reading the comments. It's become my go-to source for when I'm trying something that I haven't made before.