This potatoes and cheese sauce recipe makes a creamy, delicious potato dish. This could be a meal on its own.
Preheat oven to 350ºF.
Grease a 9x13-inch baking dish with butter.
Layer the thinly sliced potatoes in the prepared baking dish, sprinkling the sliced onion between the layers.
In a saucepan set over low heat, melt the 2 tablespoons of butter.
When the butter is melted, add the flour and allow to cook for one minute, stirring constantly.
Continuing to stir constantly, add the milk in a steady stream. Stirring until the sauce has thickened.
Add the cheese and continue stirring until the cheese has melted.
Season to taste with salt, fresh ground pepper and parsley flakes.
Carefully pour the hot cheese sauce over the potatoes in the baking dish.
Cover the baking dish with aluminum foil and transfer to the preheated oven.
Bake for 1 hour.
Remove the foil from the potatoes, and continue baking for 20 minutes, until potatoes are tender and the cheese is melted and slightly browned.