Preheat oven to 400- Spray a 2 1/2 Quart Casserole dish.

In a Large Non stck Sauce pan over medium heat; Cook bacon till crisp.

While bacon is cooking; Peel, wash and then cut about 4 Merdium/ Large russet Potatoes.

Slice Potatoes into 1/8 in. Rounds; Line half of your potatoes in the bottom of the Prepared Casserole dish.

Dice onion; Remove bacon from skillet and set aside. Add onion to same skillet and Cook 1-2 minites; until onion is tender

Add flour to the skillet with the onion-(this will be thick and clumpy)

Whisk in 2 1/2 Cups of milk; then add your ranch Packet. Whisk over medium heat until its the consistency of a thin gravy.

Pour half the sauce over half of the potatoes and spread evenly. Sprinkle half of your shreded cheese and then crumble half of the bacon over 1st layer.

Place the rest of the Potatoes over your first layer, then the rest of the sauce, Shredded cheese and Bacon.

Cover with aluminium foil and place in the oven for 45 minutes

Remove foil and bake for an additional 10-15 minutes; until starting to brown on top.

Remove from oven and allow to set 5 minutes before serving; Serve warm.