Make potato crust:

• Preheat oven to 425˚F. Heat cast iron skillet on medium heat on stove.
• Grate potatoes (I used a mixture of yellow and sweets) in food processor with grating disc or by hand with a box grater. Toss grated potatoes with 2 tablespoons oil, nutritional yeast, 1 teaspoon salt and 1/2 teaspoon black pepper.
• When skillet is hot add potatoes and spread out and up sides with back of spoon to form crust shell. Pop skillet into oven and bake crust for 15 minutes. Then remove from oven.
• Meanwhile process tofu, yogurt, 2 tablespoons oil, 1/2 teaspoon salt and 1/4 teaspoon black pepper in food processor (or blender) with regular blade until smooth. (No need to clean out bowl from grating potatoes). Set aside.
• Heat another skillet/saute pan on stove on medium heat.
• Thinly slice the red onion and rough chop or break apart the mushrooms. Sauté the onion slices in 1 tablespoon olive oil for 2 minutes then add mushrooms and cook until browned for another 2-3 minutes. Add 1/4 teaspoon salt and 1/8 teaspoon black pepper. Then deglaze pan with white wine and allow liquid to evaporate. Transfer mixture to a bowl and return skillet to heat.
• Add 1 tablespoon oil and chopped beet greens to skillet and let greens wilt for about 1 minute then transfer them to the bowl with onions and mushrooms.
• Simmer fresh green peas in a saucepan with enough water to just cover peas and 1/4 teaspoon salt for 5 minutes. If using frozen peas skip this step.
• Peel then shave beets using a mandoline slicer or thinly slice them with a knife and toss slices in 2 teaspoons oil and pinch of salt and pepper.
• Fold onion, mushrooms, greens and peas into tofu mixture, reserving some veggies to place on top of quiche.
• Layer half of the filling into potato crust. Layer beets overlapping each other into one thin layer. (Note: bake any extra slices for 5-10 minutes to make beet chips while quiche bakes) Spread rest of filling over beet layer. Arrange reserved veggies over the top.
• Bake for 30 minutes at 425˚F. Turn oven off and leave quiche in there for 5 more minutes. Then remove from oven and allow to cool and set for 20-30 minutes before slicing and serving.