Preheat the oven to 375°F (190°C). Grease a baking dish with butter.

Using a mandoline or sharp knife, slice the potatoes into thin rounds.

In a mixing bowl, whisk together the heavy cream, minced garlic, salt, black pepper, and nutmeg.

Layer half of the sliced potatoes in the greased baking dish. Pour half of the cream mixture over the potatoes and sprinkle with half of the Gruyere cheese.

Repeat with the remaining potatoes, cream mixture, and Gruyere cheese.

In a small bowl, mix the panko breadcrumbs with melted butter. Sprinkle the breadcrumb mixture over the top of the dish.

Cover the baking dish with aluminum foil and bake for 45 minutes. Remove the foil and bake for an additional 15 minutes until the top is golden brown and bubbly.

Let the dish cool for a few minutes before serving. Enjoy your Gruyere Potatoes Au Gratin!