View source for Au Gratin Potatoes

==Ingredients==
4 Potatoes, Sliced into 1/4 inch slices<br>
1 Onion, Sliced into rings<br>
3 Tablespoons butter<br>
3 Tablespoons flour<br>
1/2 teaspoon salt, pepper<br>
2 cups milk<br>
1 1/2 cups shredded cheddar cheese<br>

==Directions==
#Preheat oven to 400, butter a 1 quart casserole dish
#layer 1/2 the potatoes in the botton of the dish. Top with onion slices, add the remaining potatoes, salt and pepper to taste.
#In a medium sauce pan, melt butter over med heat. Mix in the flour and stir constantly with a wisk for one minute. Stir in the milk, cook until thickened. Stir in the cheese, cook until cheese has melted. Pour sauce over potatoes, cover with foil.
#Bake for 1.5 Hours