Lightly oil a 9x13 baking pan or cast iron skillet.
Transfer the sliced potatoes to a large glass bowl, then add the heavy cream, jalapeño peppers, garlic, parmesan cheese, salt, pepper, and chili powder. Stir to coat.
Spread the potato mix across your skillet or pan in layers.
Cover the skillet or pan with foil and bake the potatoes for 1 hour.
Remove the foil, and sprinkle the cheddar cheese on top of the potatoes. Then bake uncovered for 30 minutes or until the cheese turns a golden brown.
Remove from oven and let the dish cool for 5 minutes. Serve.