Steps
1. Preheat the oven to 375°F (190°C).
2. Cut the top off the bell pepper and remove seeds and membranes.
3. In a small pan, heat olive oil over medium heat. Add minced garlic and chopped onion, sauté until fragrant and translucent.
4. Mix in diced tomatoes, black beans, corn, cooked quinoa, salt, and pepper. Cook for 2-3 minutes until heated through.
5. Stuff the bell pepper with the quinoa mixture and place it upright in a small baking dish.
6. Sprinkle shredded cheddar cheese on top if using.
7. Bake in the preheated oven for 20 minutes until the pepper is tender and cheese is melted.
8. Garnish with fresh cilantro before serving.