Cook Or Microwave Both Sets Of Pototoes. When Cool Enough To Handle. Peel And Slice In 1/4 Inch Slices. Preheat Oven To 350 Degrees. Place Potato Slices In Large Bowl. Heat Margarine In Small Skillet. Saute Onion. Add And Remaining Ingredients To Potatoes. Mix Thoroughly Then Pour Into Oiled Shallow Baking Dish. Bake 35 Minutes.