1. Preheat oven to 400F (204C).
2. Line a baking sheet with parchment paper and add mushroom caps. Brush both sides of each with a bit of olive oil. Sprinkle the inside gills with oregano and season with sea salt and black pepper. Place in the oven and bake for 5 minutes.
3. Meanwhile, prepare your veggies.
4. Pull mushroom caps out of the oven and spoon crushed tomato sauce into the caps. Top with diced veggies and sprinkle with feta cheese. Place back into the oven and bake for 15 minutes.
5. Remove pizzas from oven. Plate and sprinkle with some red chili flakes for a bit of heat. Enjoy!
More Veggies
Top with whatever vegetables you have on hand.
No Feta Cheese?
Use goat cheese instead.
Vegan?
Sprinkle with some nutritional yeast instead of feta.
Prep Ahead
Veggies can be diced in advance and stored in airtight containers or baggies.