Preheat oven to 350°F.
Crust: Mix 1 T flax meal with 2 T water, let thicken for 10 minutes. Mix well with 3 cups defrosted, squeezed dry, fat-free hashbrowns, 1/2 tsp ea. garlic & onion powder, and 1/2 tsp salt. Press into a pie pan bottom, and a bit up the sides. Bake at 350 F till light brown, about 25-30 min.
In a pan, add onions, mushroom, and olive oil or water. Sauté for 2-3 minutes on medium heat, or until onions are translucent. Stir in 4 cups of the vegetables. Saute, covered, another 5-8 minutes with a bit of broth if needed to prevent sticking. Turn up heat for 1 minute to reduce the moisture in the pan. Let veggies cool a bit.
In a blender, place tofu, nutritional yeast, salt, turmeric, seasonings, and chickpea flour until smooth, scrapping down a few times.
In a bowl, combine the sautéed vegetables and the tofu mixture. Mix until well combined.
Pour into prepared crust.
Bake for 50–60 minutes, or until firm to the touch. If the top becomes too dark, cover loosely with aluminum foil while it continues baking.
