Preheat the oven to 350°F (180°C) and lightly grease a 9x13 baking dish with olive oil.
Prepare your filling: Add the tofu, cornstarch, nutritional yeast, turmeric, onion powder, garlic powder, salt, and black salt (aka kala namak) into your food processor and process until well mixed.
Add the soy milk or other non-dairy alternative, and process again until it reaches a smooth consistency. Set aside.
Prepare the veggies: Add the olive oil and onions to a pot and sauté the onions over a medium heat until softened.
Add the chopped sausage and sauté with the onions until lightly browned.
Add the garlic and sauté for 2 minutes until fragrant.
Add the cremini mushrooms, baby spinach, and red bell pepper, and flash fry until al dente. Remove from the heat.
Add your tofu mix and 1 cup of the grated vegan cheese to the veggies and mix until combined.
Transfer the filling to your prepared 9x13 baking dish and smooth it down evenly.
Sprinkle the remaining 1 cup of grated vegan cheese over the filling.
Place it into the oven and bake for 60 minutes until the vegan cheese is golden brown and bubbly.
Top off your vegan breakfast casserole with some chopped parsley, a sprinkle of black pepper and serve immediately.