Preheat your oven to 350 degrees. Then very thinly slice the potatoes. You can peel them if you want, but I left the skin on. You can either slice by hand or use a mandoline.
Melt the 3 tablespoons of butter and pour it over the potatoes along with garlic, ranch dressing mix, green onion, and bacon. Stir until the potatoes are evenly coated.