Preheat oven to 350 degrees.
In a small sauce pan, melt butter. Once melted add melted butter with a fork – whisking together.
Next, whisk in milk.
Cook sauce on low until smooth and boiling, whisking until thickened.
Add in salt and pepper and stir well.
Reduce heat to low and stir in 1 cup of the cheddar cheese.
Place a half of the sliced potatoes in a lightly greased 1.5 quart casserole dish (8×8 or 9×9 will work)
Pour half of the cheese sauce over potatoes.
Add a second layer of potatoes and the rest of the cheese sauce to the top of that layer
Sprinkle the remaining 1/2 cup of cheddar cheese on top.
Sprinkle the top with paprika.
Bake at 350 degrees, uncovered for 1 hour.