CHEESY BACON & CHIVE SCALLOPED POTATOES

Preheat oven to 375°F. Butter an oven-proof baking dish and set aside. Slice potatoes in 1/8" thin slices and set aside. Add butter to saucepan, and heat over medium heat. When butter is melted, add flour, whisk, and cook for 1 minute. Slowly add milk, and seasonings; whisk continuously, until sauce thickens. Turn to low and add ½ of the cheeses, stir until cheese is melted;add more milk if sauce is too thick. Layer the potatoes and onion slices in baking dish; lightly add salt & pepper on the layers. Pour the sauce over the potato layers. Top with remaining cheese. Spray aluminum foil with cooking spray, then cover the casserole dish (sprayed side down). Bake for 55-60 minutes. Remove foil and bake uncovered an additional 20 minutes. Potatoes should be tender.