I don't have a single favourite food. In terms of animal-based foods, I love beef liver or calf's liver. In terms of plant-based foods, I don't think I've ever tasted anything that's come close to matching mangosteen (at least in sweetness), though I also really like the Thai variety of snakefruit (walacca wallichiana), santol and all of the annona family fruits (it's hard to pick one in particular). While I wasn't able to finish a whole durian when I consumed it for the first time (I found difficult to consume a fruit that was custardy and tasted like onions, though I didn't dislike the taste or smell), I've been craving it recently. I wish the aforementioned fruits weren't so expensive outside of Southeast Asia.