Preheat oven to 350 F. Brown ground beef in a large skillet over medium heat, breaking it up with a spatula until it is no longer pink. Drain grease and return meat to skillet.
Add in salt, pepper, garlic powder, chili powder, diced tomatoes and drained corn. Let cook for another 5 minutes to heat through. Mix with cooked rice in a large greased baking dish.
Sprinkle shredded cheddar cheese on top and bake for 35-40 minutes.