In a large sauce pan, cook bacon, and drain pan, leaving about 2 tbsp of bacon grease. Add in cream, garlic, salt, pepper, cream of mushroom soup, cheddar and pepper jack cheese. stir until creamy and smooth. Set aside
Peel and slice potatoes to about 1/8 inch thickness. Place about half of them into a 13x9 greased baking dish. Then add half of the cheese sauce, followed by half of the bacon (crumbled) and jalapeno. Repeat this step for the second layer.
Top with Parmesan cheese and more cheddar cheese if desired. Bake at 350 for about 50 minutes. Remove foil and place in the broiler for about 3-5 minutes until top is nice and browned. Let cool for about 10 minutes and serve!
I recommend not soaking your potatoes for this dish. The starch retained by not soaking, will make sure you have thick and creamy scalloped potatoes instead of watery ones.