Cook rice according to package directions or your preferred cooking method. Set aside to cool.
¾ cups uncooked brown rice
Meanwhile, preheat oven to 400° F.
Cut the tops off the peppers and remove seeds and membranes.
6 bell peppers
Heat the olive oil in a large skillet over medium heat. Add the onion and cook, stirring occasionally, until softened, 2-3 minutes. Add the garlic and cook, stirring, for 30 seconds.
1 tablespoon olive oil, ¾ cup finely chopped yellow onion, 3 cloves garlic
Stir in the diced tomatoes, tomato sauce, black beans, corn, chili powder, cumin, garlic powder, dried oregano, salt and pepper. Reduce heat to low and simmer, stirring often, for 5 minutes.
15 ounce can diced tomatoes, 8 ounce can tomato sauce, 15 ounce can black beans, 1 cup canned corn, 2 teaspoons chili powder, 1 teaspoon ground cumin, ½ teaspoon garlic powder, ½ teaspoon dried oregano, ½ teaspoon salt, ⅛ teaspoon black pepper
Remove pan from the heat and stir in the cooked rice and ½ cup of the shredded cheese.
Pour ¾ cup of water into a baking dish. Fill bell peppers with the rice mixture and place in the baking dish. Sprinkle the remaining ½ cup of shredded cheese over the tops of the peppers.
Cover with a piece of aluminum foil that you have lightly sprayed with olive oil spray or cooking spray to prevent the cheese from sticking. Bake for 30 minutes, then uncover and bake 5 minutes more, until cheese is lightly browned and filling is hot. Serve, garnished with chopped fresh cilantro, if desired.