Start by lining slow cooker with tin foil wrap, leaving enough excess at the top to wrap around the top of the food. Spray the foil with nonstick spray.
Place a thin layer of cubed potatoes on the bottom of the crockpot and sprinkle ¼ teaspoon of ranch seasoning. Then top with ⅓ cup shredded Wisconsin Sharp Cheddar cheese, one Wisconsin String Cheese worth of circles and 2 strips of crumbled bacon. Repeat this 2 more times until all ingredients (except ⅓ cup Cheddar cheese) are used.
Cover all the potatoes with the excess foil and put on the crockpot lid. Cook on low for 8 hours or on high for 4-5 hours.
Unplug the slow cooker, uncover and top the potatoes with the remaining ⅓ cup of cheddar cheese, wrap again and let sit for about 10 minutes until fully melted.