The official The Legend of Zelda Facebook page added a new video that demonstrates exactly how cooking will work in Breath of the Wild.
In the video, we see Link light a cooking fire using a torch, and then toss a Hearty Truffle and Hearty Mushroom from his inventory into the cookpot to create Hearty Steamed Mushrooms (even humming a tune as he does so). We then see him consume it to replenish health and temporarily increase his maximum hearts. In the following scene, he harvests some Spicy Peppers and whips up a dish of Spicy Sautéed Peppers, which apparently raise Link’s body temperature to protect him from colder environments. This makes sense, as we already know that weather will play a larger role in this game and that Link will be directly affected by the ambient temperature.
Finally, he throws a lizard into the cookpot with some ‘shrooms, which results in predictably Dubious Food. The game assures you that “eating it won’t hurt you, though…probably”, but we’re not convinced. We never find out for sure, though, because that’s where the video ends.