Yes, my favorite chocolate cake ever was vegan (from The Green Planet in Houston, an incredible but now defunct vegan restaurant). But, I've never been able to make one that good. I'm not saying it can't be done, just that I haven't gotten it right yet.
Brownies, on the other hand, are a nightmare to veganize, for me. It may have to do with the kind of brownies I like, and it may just be that I've had enough bad luck that now my baking mojo is broken for making brownies. I've tried three batches in pretty quick succession, using quite different seeming recipes, and they all turned out awful; and awful in roughly the same way in all cases. Kinda like overly oily fudge, with some flour mixed in just to make it even more gross. I'm not sure, honestly. I've not tried it again lately, but will eventually. I love a good brownie. But, I was so disheartened by the first several attempts, that I've been avoiding it.
And, I can't think of a really good vegan brownie that I've ever eaten, and I know some quite good vegan cooks, and tend to frequent vegan restaurants and bakeries while traveling.
That wouldn't surprise me, and I do frequently add vinegar to my almond milk when baking to make it more like a buttermilk, even if the recipe doesn't call for it. The additional acidity when adding vinegar to a recipe that uses baking soda or baking powder can replace some of the effect of using sour cream (a very common "secret ingredient" in non-vegan chocolate cakes), which provides more leavening. It probably also alters the flavor in some way, though there are so many other competing and strong flavors, and the vinegar is such a small amount, that it probably doesn't do too much.
I don't think I've used vinegar in my chocolate cake attempts, however, so it's probably something I'll try next time.
Brownies, on the other hand, are a nightmare to veganize, for me. It may have to do with the kind of brownies I like, and it may just be that I've had enough bad luck that now my baking mojo is broken for making brownies. I've tried three batches in pretty quick succession, using quite different seeming recipes, and they all turned out awful; and awful in roughly the same way in all cases. Kinda like overly oily fudge, with some flour mixed in just to make it even more gross. I'm not sure, honestly. I've not tried it again lately, but will eventually. I love a good brownie. But, I was so disheartened by the first several attempts, that I've been avoiding it.
And, I can't think of a really good vegan brownie that I've ever eaten, and I know some quite good vegan cooks, and tend to frequent vegan restaurants and bakeries while traveling.