Preheat oven to 350°F/180°C. Grease a baking pan (I used an 8x12" pan) with some olive oil, melted vegan butter, or spray.
Cook veggies: Heat olive oil in a skillet over medium heat. Add garlic and stir for 30 seconds until fragrant. Add in chopped veggies and a pinch of salt and cook 2-3 minutes until just tender. If using onions, I recommend cooking them down first for 3-5 minutes until they start to brown, then add in other veggies. Remove from heat and let the veggies cool for a bit while you prepare the filling.
Blend filling: To a food processor, add tofu, milk, cornstarch, nutritional yeast, salt, oregano, thyme, paprika, turmeric, and pepper. Blend until smooth.
Combine: Drain any excess liquid from the veggies, then pour in tofu mixture and mix until well combined. Transfer mixture to your greased baking pan.
Bake: Place in the oven and bake 45-60 minutes until golden brown and firm to the touch. If the top is browning too quickly, cover with foil.
Cool: Cool in the pan for at least 10 minutes to allow the frittata to firm up a bit more.
Serving: The frittata is delicious as is, but for a more well rounded meal, serve with some avocado and toast, oatmeal, or a smoothie.
Storing: To store leftovers, let the frittata cool completely, then cover and store in the fridge for up to 5 days.
Notes
Tofu: Firm tofu can be used as well, but it will need to be pressed first to remove excess liquid.