Steps
1. Preheat the oven to 375°F (190°C).
2. Slice the top off the bell pepper and remove the seeds.
3. In a mixing bowl, combine cooked quinoa, black beans, corn, diced tomatoes, cumin, chili powder, salt, and pepper.
4. Stuff the mixture into the bell pepper.
5. Place the stuffed pepper upright in a baking dish and drizzle with olive oil.
6. Cover with foil and bake for 25 minutes.
7. If using cheese, remove the foil, sprinkle cheese on top, and bake for an additional 5 minutes until the cheese is melted and bubbly.
8. Let cool slightly before serving.