Scalloped Potatoes

Foolproof scalloped potatoes.

===== Ingredients =====
-4-5 medium Idaho or Yellow potatoes
-3tbsp butter
-3tbsp flour
-1.5c milk
-1tsp salt
-dash of cayenne
-1c grated cheddar
-1/2c grated cheese, for top
-paprika

===== Instructions =====
1. Slice potatoes about 1/16th of an inch thick, preferably with a mandoline.
2. In a medium sauce pan, melt butter and add in flour. Stir constantly for a minute or two to make the roux.
3. Add milk, season with salt and cayenne. Cook on medium-low until sauce is smooth and starting to thicken.
4. Mix in 1c of cheese, stir until combined. Remove from heat.
5. Arrange half of the potatoes in a casserole dish in a neat layer. Pour half of the cheese sauce over the layer. Repeat with another layer of potatoes and cheese sauce. Sprinkle the remaining shredded cheese over top, with some paprika for color.
6. Bake uncovered for 50 minutes to an hour at 350F.