Preheat your oven to 350 degrees Fahrenheit. Lightly grease a 9×13 inch baking dish.
In a large bowl, beat the softened cream cheese until smooth.
Add the melted butter, creamed corn, drained whole kernel corn, corn muffin mix, sour cream, eggs, and salt to the bowl. Mix until just combined. Do not overmix.
Fold in the shredded cheddar cheese.
Pour the batter into the prepared baking dish.
Bake for 45 to 55 minutes, or until the top is golden brown and a toothpick inserted near the center comes out clean.
Let the casserole rest for 5 minutes before cutting and serving.
Notes
For a slow cooker version, mix ingredients and cook on low for 3 to 4 hours or on high for 1.5 to 2 hours.
You can substitute Monterey Jack cheese for cheddar if you prefer a milder flavor.
This is a great kid friendly side dish that pairs well with weeknight meals.