Preheat your oven to 350°F (175°C).

In a food processor, blend the firm tofu, cornstarch, nutritional yeast, turmeric, onion powder, garlic powder, salt, black salt, and soy milk until smooth.

Heat a skillet over medium heat with olive oil. Sauté the chopped onion and crushed garlic for 3-4 minutes until softened.

Add the sliced cremini mushrooms and chopped red bell pepper, and sauté for another 3-5 minutes until softened.

Stir in the chopped baby spinach and cook until just wilted, about 1-2 minutes.

Combine the sautéed vegetable mixture with the blended tofu batter until well mixed.

Smooth down the mixture in an oven-safe skillet or transfer to a pie dish.

Sprinkle sundried tomatoes and red onion on top if desired.

Bake for 40 minutes until the top is firm and golden.

Cool for 10 minutes before slicing into wedges.