Preheat the oven to 350°F and lightly grease a casserole dish, then prepare the bell peppers by trimming the bottoms, removing the tops, and clearing out the seeds so they stand upright.

Place the peppers in the casserole dish and bake them until slightly softened, allowing them to hold their shape while becoming tender.

In a large skillet, cook the ground beef over medium-high heat until browned, breaking it into small pieces as it cooks.

Add the chopped onion and celery, then cook until softened, followed by the garlic which should be stirred in just until fragrant.

Stir in the diced tomatoes, green chilis, cumin, chili powder, salt, and pepper, mixing well so the flavors combine evenly.

Add the black beans, corn, uncooked rice, and chicken broth, then cover and cook until the rice is tender and has absorbed most of the liquid.

Spoon the prepared filling into the pre-baked peppers, packing it in firmly and slightly mounding the tops.

Place a slice of provolone cheese over each pepper, then bake until the cheese is melted and lightly golden.

Remove from the oven, garnish with fresh cilantro, and serve warm.