Here is my recipe for Scalloped Potatoes. Very yummy and not too expensive to make.
4 c sliced potatoes (as thin as you can...but keep them uniform) 3 T butter/margarine 3 T flour 1 1/2 c milk 1 t salt bit of pepper dash of cayenne 1 c grated chedder to put in sauce (can also use velveeta) 1/2 c additional cheese for topping (you can also add bread crumbs under the cheese if you need to use some up) paprika for color
Heat oven to 350 degrees. In a saucepan melt your butter. Add the flour to make rouxe when the butter is melted. Add milk all at once and stir constantly. Add seasonings to sauce and let it thicken. After sauce is thickened, remove from heat and add the cup of cheddar.
In Qt baking dish (or larger) put down a layer of potatoes (about half), then cover with half the sauce. If you are using bread crumbs, you can put some of them here in between layers. Now repeat, potatoes, sauce...then put the toppings on. Breadcrumbs, if using, and then 1/2 c cheese.
Bake for about an hour. I have also used leftover baked potatoes for this. (Reduce liquid if using baked and time is just until heated through and bubbly)