Preheat oven to 375 deg F and line a baking dish with parchment paper (or just grease the pan with olive, coconut, or other 90/10 approved oil). We used an 9 x 13 baking dish. If you use a smaller dish (such as an 8 x 8), it will be thicker and may take more time. It just depends on how you want it.
Add eggs and coconut milk to a bowl and whisk thoroughly.
Add all of the dry spices to the egg mixture and whisk again to combine.
Add the mushrooms, peppers, and green onions to the egg mixture and stir to combine. You can add the pepperoni here or add to the top near the end.
Pour the whole mixture into the baking dish.
Bake at 375 for 20-25 minutes (depending on thickness of your quiche). You want the quiche to be starting to set on the top but not quite done in the center.
Remove from oven. Add tomato sauce, then pepperoni (if not added earlier), and cover with mozzarella (optional).
Return to oven and bake an additional 10 minutes or until quiche is set in the center.