Preheat oven to 350 degrees.

Place peppers over a hot grill, gas burner or under a broiler and char all over -- about 10 minutes. Turn regularly to ensure the peppers are completely blackened. When done, place peppers in a large mixing bowl and cover with foil or cling wrap and let them sit for about 20 minutes until cool enough to handle. When cooled, peel the skin off of the peppers.

While peppers are cooling, heat olive oil in a large skillet over medium heat. Sauté onion pieces until translucent -- about 5 minutes. Add diced sweet potato and cook until tender -- about 15 minutes. Add garlic, corn, beans, ground cumin, dried oregano, chili powder, salt, pepper and cook until heated through -- about 5 minutes. Take off heat and pour into a large mixing bowl.

Reserve about 6 tablespoons of cheese for topping the stuffed peppers and add the rest to the vegetable mixture. Stir to mix.

Take cooled, peeled peppers and make a slit along the side of each one lengthwise, making sure you do not cut the peppers in half. Scoop out the seeds and veins with a small spoon. Scoop 1/6th of the mixture into each pepper. Place peppers in a lasagna pan or similar baking dish and top each with about 1 tablespoon of the reserved cheese. Bake for 10 - 15 minutes or until the filling is heated through and the cheese is melted.