Combine the sliced potatoes, cream, garlic, gruyere cheese, nutmeg, salt, and pepper in a large bowl until thoroughly mixed. Ensure the potatoes are seasoned and coated by tasting some of the cream after mixing it.
transfer the mixture to a deep 13x9 casserole pan sprayed with non-stick spray and flatten out with a spoon to make it level.
Cover in foil and bake in the oven at 400° for 80 to 90 minutes.
Remove the foil and evenly sprinkle on the breadcrumbs and cheese, completely coating the sliced potatoes.
Drizzle on the melted butter and place back in the oven for 20 to 25 minutes or until golden brown on top and cooked throughout.
Let cool at room temperature for 5-10 minutes before serving.
Notes
Make-Ahead: These are best eaten right away. However, you can make them 1 day ahead of time by following my instructions above.How to Store: I like to store these in the refrigerator covered in plastic for up to 4 days. I also cover and freeze them for up to 2 months. Simply thaw them for 1 day in the refrigerator before reheating them.How to Reheat: To reheat them, add your desired portion to a pan, cover with foil, and bake in the oven at 375° for 20-25 minutes or until hot. In addition, you can simply add them to the microwave and heat them until hot.You can also feel free to use Yukon potatoes as well.When it’s done cooking in the oven, The outside edges of the pan should be bubbling.You can substitute half and half for the heavy cream.These potatoes au gratin are meant to feed many people, so feel free to cut the recipe in half.If you do not have a deep 13x9 casserole dish, please use two standard-size 13x9 dishes.