Step #2 Coat a 2-quart baking dish with cooking spray.
Step #3 Melt butter In a large-ish frypan over med-heat/flame; add in onion & cook stirring every once in awhile until onion begins to brown (about 5 mins).
Step #4 Stir in flour, then slowly add in milk.
Step #5 Add in potatoes; stir this to mix; bring to a boil.
Step #6 Stir in 3/4 c cheese, salt & black pepper.
Step #7 Pour mixture into prepared baking dish then spread out.
Step #8 Bake for 1 hr uncovered.
Step #9 After 1 hr cooking time cover with foil wrap & continue to bake another 20 mins more.
Step #10 Change oven to broil heat.
Step #11 Sprinkle top the remaining cheese over potatoes & broil 6-inches from heat until the cheese is golden (about 1-2 mins).
Step #12 Cool 5 mins before serving.
Enjoy the Weight Watchers Au Gratin Potatoes 3 Pts (Low-Fat) recipe