Set your oven to 350°F (175°C). Grease a 9×9-inch or 9×13-inch baking dish with butter or nonstick spray to keep the casserole from sticking.

In a large bowl, stir together the drained whole kernel corn, cream-style corn, sour cream, melted butter, and eggs until smooth and fully combined.

Pour in the Jiffy Corn Muffin Mix and stir gently until just blended. Don’t overmix—this keeps the casserole soft and tender.

If you’re adding cheddar, fold it in gently for extra creaminess and a golden, cheesy top.

Pour the mixture into your prepared dish and spread it out evenly with a spatula.

Bake for 45–55 minutes, until the top is golden brown and the center is set. A toothpick inserted in the middle should come out mostly clean with just a few moist crumbs.

Let it rest for 5–10 minutes before serving. This helps the casserole firm up and makes it easier to slice.