> I had a friend who complained that no matter how tofu was cooked, it tasted like cubes to him, so I've dealt with this problem a few times before

Sounds like a textbook case of synaesthesia to me.

If I heard a complaint like that, I'd make a tofu scramble, which to me means smashing the block of tofu into little bits with a spatula rather then dicing it. Definitely does not result in cubes! Then stir-fry it with whatever ingredients you see fit.