Cut the tops off the bell peppers and remove the seeds and membranes. Place them upright in a baking dish.
In a medium pot, combine the quinoa and vegetable broth. Bring to a boil, then reduce the heat to low, cover, and simmer for 15-20 minutes until the quinoa is cooked and fluffy.
In a large skillet, heat a drizzle of olive oil over medium heat. Add the diced onion and sauté for 3-4 minutes until translucent.
Add the minced garlic to the skillet and cook for an additional 1 minute until fragrant.
Stir in the black beans, corn, drained diced tomatoes, cumin, chili powder, smoked paprika, salt, and pepper. Cook for about 5 minutes until heated through.
Once the quinoa is done, fluff it with a fork and add it to the skillet mixture. Stir well to combine all ingredients.
Divide the quinoa mixture evenly among the prepared bell peppers, pressing down gently to pack them.
Top each stuffed pepper with shredded cheese.
Cover the baking dish with aluminum foil and bake for 25 minutes. Remove the foil and bake for an additional 10-15 minutes until the peppers are tender and the cheese is bubbly and golden.
Remove from the oven, let cool for a few minutes, and garnish with fresh cilantro before serving.
Notes
Feel free to customize the spices and toppings to your preference.