Preheat oven to 425 degrees. Line a large baking sheet with parchment paper.
Place red bell peppers, yellow bell peppers, red onion, and yellow corn on the baking sheet. Drizzle with olive oil and season with salt and pepper. Mix vegetables and oil. Push the vegetables to the sides, clearing out a space in the middle.
Place the chicken into the cleared out areas of the baking sheet.
In a small bowl, whisk together the chili powder, garlic, salt, ground cumin, oregano, and black pepper. Then whisk in vegetable oil.
Spoon the marinade evenly over chicken breasts, coating full surface of one side of the chicken.
Bake for 25 minutes or until chicken and vegetables are cooked through. Remove from oven, cover with foil and let rest for 10 minutes. Slice chicken and serve with tortillas, rice, salsa, sour cream, beans, and cheese.