Get the oven to 350 degrees.
Use a nonstick cooking spray to coat a 9×13” baking dish.
Cook the ground beef and onion in a large pan until the meat is done.
Peel and cut the potatoes into pieces that are about ½" thick.
Spread out the potatoes in a single layer on the baking pan's base.
Season with pepper and salt.
Distribute the meat mixture equally over the potatoes and top with about 3/4 of it.
Add a third of the shredded cheese on top.
Do this twice more in a layered fashion.
The remaining cheese should be layered on top.
Bring the Cheddar cheese soup mix, milk, and evaporated milk to a boil in a saucepan. Season with salt and pepper to taste.
Top the steak and potato mixture with the soup mix.
Place the baking pan in the oven and cover it securely with aluminum foil.
The recommended baking time is one hour.
To get a golden crust on the cheese, remove the foil and bake for another fifteen minutes.
You may have to roast the potatoes for a little longer if they're thicker. Hope you like!