Preheat oven to 400 degrees F. Cut off the top 1/2” of the peppers and put aside. Scoop out the seeds from the peppers. Discard stems and chop the pepper tops.
Warm the oil in a large skillet over medium heat. Add onions, garlic and chopped pepper pieces. Sauté until tender, about 5-7 minutes. Transfer to a large bowl.
Mix in rice, chiles, beans, corn, chili powder, and cumin. Season to taste with salt and pepper.
Fill peppers with the “beef” and rice mixture. Stand the filled peppers in a single layer in a shallow baking dish. Add 1/2 cup of water to the base of the dish. Cover with foil.
Bake the peppers for 15 minutes. Uncover and continue baking 5 more minutes. Option to add plant-based cheese. Sprinkle with fresh cilantro and serve warm.