Prep the peppers: Heat oven to 400°F (200°C). Slice a thin piece off the bottom of each pepper so they sit flat if needed.
Cut off the tops, remove seeds and membranes. Lightly season the insides with salt and pepper.
Pre-bake for tenderness: Place peppers upright in a baking dish. Add a splash of water to the pan, cover tightly with foil, and bake for 12–15 minutes to soften slightly.
This helps them cook evenly later.
Cook the grains: If you haven’t already, cook brown rice or quinoa according to package directions. You’ll need 1 cup cooked. Fluff and set aside.
Sauté aromatics: In a large skillet, warm olive oil over medium heat.
Add onion with a pinch of salt and cook 4–5 minutes until translucent. Stir in garlic and cook 30 seconds until fragrant.
Brown the chicken: Add ground chicken. Break it up and cook until no longer pink, 5–6 minutes.
Season with smoked paprika, oregano, cumin, red pepper flakes, salt, and black pepper.
Build the filling: Stir in crushed tomatoes, chicken broth, black beans, and corn. Simmer 5 minutes to thicken slightly. Fold in the cooked rice or quinoa.
Taste and adjust seasoning. The mixture should be hearty and spoonable, not soupy.
Stuff and top: Remove peppers from the oven. Spoon the hot filling into each pepper, packing it gently.
Top with mozzarella and a sprinkle of Parmesan if using.
Bake to finish: Return to the oven, uncovered, and bake 15–18 minutes, until the peppers are tender and the cheese is melted and lightly browned.
Garnish and serve: Let cool for 5 minutes. Sprinkle with parsley or cilantro. Serve with lime wedges for brightness.