3 tbsp. butter
2 tbsp. flour
2 c. milk
1 tsp. salt
1/4 tsp. pepper

Place butter in 1 quart glass measuring cup or bowl. Microwave at High for 1-2 minutes. Blend in flour and seasonings. Gradually stir in milk. Microwave at High for 8-10 minutes, stirring after 4 minutes. 2 tbsp. minced onion

Layer half of potatoes, onion and sauce in greased 2 quart casserole. Repeat layers and cover. Microwave at medium high for 17-19 minutes. Remove and let stand 5 minutes before serving.