Preheat oven to 450 F.
Defrost the pizza crust.
Heat a large sauce pan over medium high heat. Add two tablespoons of water and then the onions and peppers. Saute for 10-12 minutes until softened adding more water 2 tbs at a time, if necessary.
Spread the tomato sauce evenly on the pizza crust.
Layer with spinach and then the onions and pepper mixture.
Distribute the olives evenly over the top.
Bake for 8-10 minutes until crust begins to brown.
Sprinkle with red pepper flakes and nutritional yeast to taste.