Preheat a heavy-bottomed pan to medium heat. Add 1 Tb of grapeseed or vegetable oil.

Chop tofu into cubes. Ensure they are drained. Add to pan, and sear lightly on each side for a couple of minutes. Turn over, and repeat on the other sides. You're not looking to brown the tofu, just keep it from falling apart. Add salt and pepper to taste, and remove from the pan. Set aside.

Meanwhile, chop onion into medium-sized pieces. Add more oil to the pan, and on medium-low heat, saute the onion until translucent.

Slice zucchini into thin half-crescents. Slice mushrooms into slices of a similar width to the zucchini. Add to pan with the onion, cover, and cook on low-medium heat until zucchini softens, about 15 minutes, stirring occasionally. Remove cover, increase heat to medium-high, add tofu and stir. Cook for another 10 minutes to allow water to cook out of the vegetables. If vegetables are beginning to stick to the bottom, add a bit more oil.

When vegetables have reduced to a stewy consistency, add vinegar, salt and pepper. Taste. If texture is to your liking, remove from heat now, or reduce heat and continue to cook on a low-medium flame. When ready to remove from flame, add vegan sour cream and stir. Taste and adjust flavours as necessary.

Serve with brown rice or quinoa, topped with fresh parsley or cilantro, and with a bit more vegan sour cream on the side. Oh yeah, and don't forget the hot sauce.