Scrub and pierce potatoes; place on a microwave-safe plate.
Microwave on high for 15-20 minutes or until tender.
In a saucepan, melt butter.
Stir in flour,garlic powder,salt and pepper until smooth;gradually whisk in milk.
Bring to a boil;cook and stir for 2 minutes or until thickened.
Add the processed cheese and bacon;stir until cheese is melted.
Remove from heat;set aside.
Cut the potatoes into 1/4" slices.Place a third of the slices in a greased 9 X 13" baking dish;top with a third of the cheese sauce.
Repeat layers twice.
Sprinkle with cheddar cheese and onions.
Bake uncovered, at 350* for 15 minutes or until cheese is melted.
YIELD: 10-12 servings
Not a NESTLÉ®-tested recipe.