Preheat your oven to 350°F (175°C).

In your food processor, combine the firm tofu, cornstarch, nutritional yeast, turmeric, onion powder, garlic powder, and salt. Gradually add the soy milk and blend until smooth.

Heat olive oil in a skillet over medium heat. Add the chopped onion and cook for 3-4 minutes until softened.

Stir in crushed garlic and cook for an additional minute.

Add sliced cremini mushrooms and chopped red bell pepper. Cook for 5-6 minutes until tender.

Fold in the chopped baby spinach and stir until just wilted.

Combine sautéed vegetables with the tofu mixture and stir thoroughly until well combined.

Pour the frittata mixture into your skillet or pie dish. Optional: sprinkle sundried tomatoes and red onion on top.

Bake for 40 minutes, or until the top is firm and golden-brown.

Remove from oven and let cool for 10 minutes before slicing.