1. Preheat your oven to 350 degrees. Set aside a casserole dish for the bell peppers.
2. Slice the tops off of the bell peppers, and remove the insides and seeds. Place in casserole dish upright, tightly packed against each other. Set aside.
3. In a skillet over medium high heat, heat the coconut oil. Add in the onions and garlic and sauté until slightly translucent, about 5 minutes.
4. Add in the black beans, corn, chili powder, ground cumin, sea salt, black pepper, parsley and quinoa. Stir to combine. Add the marinara sauce and 1 13/4 cups of the cheese on top. Stir again to combine and let sit until cheese has melted slightly, about 3 minutes. Remove from heat.
5. Stuff each of the peppers with the mixture, packing them tightly. Sprinkle the cheese on top of the peppers.
7. Bake for 40 minutes until tops are golden brown. You can also optionally lightly broil the tops.