Preheat Oven: Preheat your oven to 350°F (175°C). Lightly grease a 9x13-inch baking dish.

Mix Wet Ingredients: In a large mixing bowl, beat the softened cream cheese until smooth. Add the melted butter, granulated sugar, milk, and beaten eggs, and mix until well combined.

Add Corn and Muffin Mix: Stir in the drained whole kernel corn, creamed corn, and corn muffin mix. Mix until just combined.

Season and Add Cheese: Add salt and black pepper to the mixture. If using, fold in the shredded cheddar cheese.

Bake: Pour the mixture into the prepared baking dish and spread it out evenly. Bake in the preheated oven for 45-50 minutes, or until the top is golden brown and the center is set.

Cool and Serve: Allow the casserole to cool for a few minutes before serving.