1. Center a rack in the oven and heat to 400. Cook bacon in a large skillet over medium-high heat until crisp, 5 to 7 minutes. Transfer bacon to a paper-towel-lined plate and drain all but 2 tablespoons fat from skillet. Add leeks to skillet and cook, stirring occasionally, until softened, 5 to 7 minutes. Season leeks with salt and pepper to taste.
2. Meanwhile, combine potatoes and heavy cream in another large skillet over medium heat and bring to a simmer. Cook, stirring occasionally, until potatoes are just tender, 10 to 12 minutes. Season with salt and pepper to taste.
3. Using a slotted spoon, transfer half of the potatoes to a greased 9x13" baking dish (or other 3-quart gratin dish) and spread into an even layer. Layer evenly with leeks, bacon, cheese, thyme, and nutmeg. Cover with remaining half of potatoes and pour any cream remaining in the skillet over top.
4. Mix together breadcrumbs and melted butter until evenly coated and sprinkle over potatoes. Bake until potatoes are fork-tender and breadcrumbs are browned, 25 to 30 minutes. Let sit 10 minutes before serving.
Source: Hannaford fresh Magazine, March - April 2017