Preheat your oven to 350°F and prepare a 9x13 inch baking dish by spraying it with cooking spray.
In a large mixing bowl, combine the Jiffy cornbread mix, melted butter, eggs, cream style corn, whole kernel corn, sour cream, and sharp cheddar cheese.
If you like a bit of heat, add chopped jalapenos to your preference and mix everything together until the mixture is smooth and well combined.
Pour the mixture into the prepared baking dish. If desired, sprinkle additional jalapenos and extra cheese on top.
Bake in the preheated oven for 45 minutes. After this time, check the casserole with a toothpick; if it comes out clean, it's done. If not, continue baking for an additional 10 to 15 minutes until it is firm and set.
Once baked, let the casserole sit for a few minutes before serving.
