Preheat oven to 350°.
Combine flour, salt and pepper in small bowl and set aside.
Pare and slice potatoes and onions.
Grease shallow casserole dish.
Place 1/1 of potatoes in dish.
Sprinkle half flour mixture over potatoes
and then add 1/2 onions, half butter, half cheese.
Repeat using rest. Pour milk over all.
Cover and bake for 30 min.
Remove cover and bake for 45 min.-1 hr.
until potatoes are tender and lightly browned.