Preheat your oven to 375°F (190°C) and lightly butter a 9x13 inch baking dish.

In a large bowl, combine the thinly sliced potatoes, heavy cream, minced garlic, grated Gruyere cheese, nutmeg, salt, and black pepper, ensuring the potatoes are evenly coated.

Arrange the mixture evenly in the prepared baking dish.

Bake for 45-50 minutes, or until the potatoes are tender and the top is golden brown and bubbly.

**Tip 1: Use a Mandoline for Slicing:** Achieve uniform and thin potato slices quickly by using a mandoline, which will also ensure even cooking and faster tenderness.

**Tip 2: Par-Cook Potatoes (Optional but Recommended):** For an even faster cook time, briefly boil potato slices for 5-7 minutes until slightly tender, then drain and proceed with the recipe.

**Tip 3: Elevate Flavor with Fresh Herbs:** Garnish the dish with fresh chopped parsley or chives before serving to add a burst of freshness and color, enhancing the overall presentation and taste.