Scalloped Potatoes - cooking recipe

Ingredients

2 lb. potatoes
2 Tbsp. butter
3 Tbsp. flour
1 tsp. salt
1/4 tsp. pepper
2 1/2 c. milk
1 small onion, finely chopped (about 1/4 c.)
1 Tbsp. butter

Preparation

Peel potatoes and cut into thin slices, enough to measure 4 cups.
Heat 3 tablespoons butter in saucepan over low heat.
Blend in flour, salt and pepper.
Cook, stirring constantly, until smooth and bubbly; remove from heat.
Stir in milk.
Heat to boiling, stirring constantly.
Boil and stir 1 minute.