3 tablespoons butter
2 tablespoons flour
1 teaspoon salt
1/4 teaspoon pepper
2 cups milk
3 1/2-4 cups thinly sliced potatoes (about 3 medium)
2 tablespoons minced onion

place butter in 1 qt microwave-safe dish. microwave on HIGH 1-2 minutes or until melted. blend in flour and seasonings. gradually stir in milk. microwave on HIGH 8-10 minutes, stirring after 4 minutes.

layer 1/2 of the potatoes , onion and sauce in a greased 2 qt dish. repeat layers. cover.

microwave on MED-HIGH 24-28 minutes. let stand 5 minutes.