Preheat your oven to 375°F (190°C).

Peel and slice sweet potatoes into uniform rounds about ¼ inch thick. Boil for 10–15 minutes until fork-tender. Drain and cool slightly.

In a greased baking dish, layer half of the sweet potato slices at the bottom and sprinkle half of the cranberries on top.

In a mixing bowl, combine heavy cream, brown sugar, cinnamon, salt, and pepper. Whisk until smooth. Pour half over the layered sweet potatoes and cranberries.

Repeat layering with remaining sweet potato slices and cranberries, then pour remaining cream mixture on top.

Sprinkle shredded Gruyère cheese and breadcrumbs evenly over the top.

Bake for 30–35 minutes until golden brown and bubbling.

Cool for about 10 minutes before serving.