Place bell peppers into a baking dish, cut sides up. Set aside.
In a large bowl, gently mix together quinoa, corn, tomatoes, black beans, green chiles, 1/2 cup pepper jack cheese, cilantro, cumin, garlic powder, chile powder, onion powder, salt, and pepper until well combined.
Spoon mixture evenly into each of the bell pepper cavities until filled. Sprinkle remaining 1/2 cup cheese over tops of filled peppers, dividing evenly among the peppers.
Bake uncovered in oven for 30 minutes or until peppers are tender and filling is heated through. Enjoy immediately.