Preheat your oven to 350 degrees F (175 degrees C).
In a large bowl, stir together the whole kernel corn, cream-style corn, and cornbread mix.
Add in the sour cream and melted butter, and mix until well combined.
Pour the mixture into a greased 9x13 inch baking dish.
Bake in the preheated oven for 45 minutes, or until the top is golden brown and the center is set.
Optional: During the last 10 minutes of baking, sprinkle the shredded cheddar cheese on top, if using.
Let cool for a few minutes before serving. Enjoy!