Preheat oven to 350°F (175°C).

Brown ground beef in a large skillet over medium-high heat.

Add diced onion to the skillet and cook until softened.

Drain off any excess grease.

In a large bowl, combine the browned ground beef and onion with evaporated milk, tomato soup, cooked macaroni, and cream-style corn.

Season with salt and pepper to taste.

Stir in grated Cheddar cheese until well blended.

Pour the mixture into a greased casserole dish.

Bake in the preheated oven for 30 minutes, or until golden brown and bubbly.

Let stand for 10 minutes before serving.