Preheat your oven to 350°F (175°C) and grease a 9x13 inch baking dish.
In a large mixing bowl, combine both boxes of cornbread mix, cream-style corn, and drained whole kernel corn.
Add sour cream, eggs, and melted butter to the mixture. Stir until well combined.
Mix in half of the shredded cheese, garlic powder, salt, and pepper.
Pour the mixture into your prepared baking dish, spreading it evenly.
Top with remaining cheese.
Bake for 45-50 minutes, or until the center is set and the top is golden brown.
Let it rest for 10 minutes before serving.