Scalloped Potatoes - cooking recipe

Ingredients

6 medium potatoes or 4 c. sliced
3 Tbsp. butter
2 Tbsp. flour
3 c. milk
2 1/2 tsp. salt
1/4 tsp. pepper
2 Tbsp. chopped onion
Au Gratin - 2 c. grated cheese

Preparation

Pare potatoes, slice thin.
Melt butter and add onion to saute.
Add flour and blend.
Gradually add milk.
Cook until smooth and thickened.
Add remaining ingredients (including cheese if making au gratin potatoes).
Simmer 7 minutes.
Pour into greased baking dish.
Bake uncovered at 350 degrees for 1 hour.