Preheat oven to 375 °F (190 °C). Lightly grease a 9×13‑inch baking dish.

In a small saucepan, combine rice and vegetable broth, bring to a boil, then reduce heat to low, cover, and simmer 15 minutes or until liquid is absorbed. Fluff with a fork and set aside.

While rice is cooking, heat olive oil in a skillet over medium. Sauté onion for 3–4 minutes until softened. Add garlic and cook 30 seconds until fragrant.

Stir in zucchini, corn, cumin, chili powder, paprika, salt, and pepper. Cook 4–5 minutes until vegetables are just tender.

Add cooked rice and black beans to skillet, stirring to combine. Adjust seasoning as needed.

Arrange bell peppers upright in the baking dish. Spoon rice-vegetable mixture into each until well packed.

Cover dish with foil and bake 20 minutes. Remove foil, sprinkle cheese over peppers, and bake uncovered an additional 10 minutes, or until cheese is melted and peppers are tender.

Remove from oven, sprinkle with cilantro or parsley, and let rest 5 minutes before serving.