Preheat your oven to 350°F (175°C).

In a large bowl, combine the whole kernel corn, creamed corn, sour cream, melted butter, cheddar cheese, eggs, and Jiffy cornbread mix. Stir until fully blended and smooth.

Grease a 9x13 inch baking dish with butter or cooking spray. Pour the corn mixture into the dish, spreading it evenly.

Bake uncovered for approximately 45 minutes, until the edges are golden brown and the center feels set.

Let the casserole rest for about 10 minutes before slicing and serving.