Preheat oven to 400°F. Although you may slice the potatoes using a sharp slicing knife, it is best to use a mandolin to achieve the thinness required. Slice potatoes either cross or long ways, working quickly to prevent potatoes from oxidizing. Boil potatoes in lightly salted water until tender, approximately 1½ minutes after water returns back to a boil. Do not overcook. Drain potatoes in a colander under cold running water then set aside to drain thoroughly. In a large skillet, sauté bacon over medium-high heat until golden brown and crispy. Drain bacon on paper towels and reserve. Pour off all but 2 tablespoons of bacon fat then add leeks. Sauté leeks 3–5 minutes or until softened then add reserved bacon and white wine. Simmer 2–3 minutes or until wine reduces. Season to taste using salt, black pepper and granulated garlic. Set aside. In a large saucepan, combine milk, minced garlic and bay leaf then simmer over medium-high heat 5–7 minutes then remove bay leaf. Whisk in cream cheese and Boursin cheese, a little at a time, stirring until smooth and thick, approximately 5 minutes. Season to taste with salt, black pepper, granulated garlic, nutmeg and cayenne pepper then set aside. Coat a 9" x 9" baking dish with nonstick cooking spray. Coat bottom of pan with ⅓ cup cheese sauce and cover with 2 layers of potato slices, overlapping slightly. Top potato slices with ⅓ cup cheese sauce, ½ cup leek filling and ¼ cup Swiss cheese. Follow with 2 more layers of potato slices then add more leek filling, sauce and cheese. Continue building 2 more layers, ending up with a double layer of potatoes on top. Spread ½ cup of cheese sauce over last potato layer and sprinkle with remaining Swiss cheese. Cover pan with foil and bake 45 minutes. Remove foil then bake an additional 15–20 minutes or until lasagna is tender when pierced with a knife and brown on top. Remove from oven and let stand 30 minutes before cutting.