Preheat oven to 375˚.
Lay peppers cut side up in an oven proof casserole dish and spray with oil.
Bake 30 minutes and remove from oven.
While the peppers are baking, heat oil in a large skillet.
Sauté onions till soft and add the beef breaking it apart and cooking till no longer pink.
Remove the pan from the heat and stir in the cauliflower rice, marinara, nutritional yeast, and spices stirring well.
Stuff the peppers with the mixture and top with shredded dairy-free mozzarella.
Return to oven and bake 20 minutes more.
Enjoy!