From: Linda/BDT Burbank, CA
POTATOES AU GRATIN
4 tblsp butter
3 tblsp all-purpose flour
2 tsp salt
1 tsp black pepper
2 cups milk
5 large potatoes, peeled and sliced into medium-thin slices
2 onions, peeled and chopped
1-1/2 to 2 lbs * sharp cheddar cheese, cubed or sliced
In a medium saucepan, melt butter and add flour, salt and pepper. Pour in the milk and stir frequently till thickened. Set aside.
Preheat oven to 350 degrees. Lightly butter a large casserole (3-1/2 to 5 quart).
Layer 1/4 of the potatoes, 1/4 of the onion, 1/4 of the cheese and sprinkle with salt and pepper. Repeat the next layer. Then, on top of the second layer, pour half the white sauce over (be a little reserved 'cuz you want the majority of the white sauce on top of the finished casserole). Then, again, repeat the next layer with potatoes, cheese, onion, salt and pepper. Repeat the final layer with same. Pour the remaining white sauce over the top, making sure you cover all. Sprinkle the final product with salt and pepper.
Cover and bake 1 hour. Then, remove the cover and bake for another hour. Don't worry if it gets a little dark on top.
For leftovers, I put some of the casserole in a microwaveable dish. Pour a little milk over and stir. Zap in the microwave on high until heated through!