Ingredients:
- 3 lbs Russet potatoes
- 1 clove garlic, peeled and halved
- 1.5 cups heavy cream
- 1 cup whole milk
- 2 cloves garlic, smashed
- 3 sprigs fresh thyme
- 0.5 tsp ground nutmeg
- 1.5 tsp sea salt
- 0.5 tsp cracked black pepper
- 1 cup Gruyère cheese, finely grated
- 2 tbsp unsalted butter, cubed
Instructions:
- Rub the inside of a 9x13 inch ceramic baking dish with the halved garlic clove, then grease lightly with butter.
- In a large saucepan, combine heavy cream, milk, smashed garlic, thyme, nutmeg, salt, and pepper. Bring to a simmer over medium heat, then remove from heat and let steep for 5 minutes.
- Peel the potatoes and use a mandoline to slice them into 1/8th inch (3mm) rounds. Do not rinse the slices to preserve the starch.
- Preheat oven to 375°F (190°C). Arrange potato slices in the baking dish in neat, overlapping rows.
- Strain the infused cream mixture through a fine-mesh strainer over the potatoes, discarding the aromatics. Ensure potatoes are mostly submerged.
- Cover the dish with foil and bake for 45 minutes. Remove foil, sprinkle evenly with grated Gruyère cheese and dot with the cubed butter.
- Bake uncovered for an additional 30 minutes until the top is mahogany-colored and the potatoes are tender when pierced with a knife.