Ingredients
Equipment
Method
- Preheat the oven to 400℉.
- In a well-seasoned 12-inch cast-iron (or other ovenproof) skillet, add the half-and-half, garlic, bay leaves, 2 tablespoons unsalted butter, kosher salt, and a few grinds of black pepper. Heat over medium until it just begins to simmer. Turn off the heat and let it sit for a few minutes so the garlic and bay can infuse the cream.
- Use a mandoline or a sharp knife to slice the potatoes very thinly. I prefer to peel them, but the skins can be left on if you like that look. Remove the bay leaves from the cream and discard them. Add the sliced potatoes to the cream and use a silicone spatula to spread them into an even layer. The cream should just barely cover the potatoes. If it does not, add up to ½ cup more. Taste the cream mixture to ensure it is lightly scented with garlic and well salted.
- Cover the pan and cook the potatoes over medium heat until they begin to soften, about 10 minutes. Scrape the bottom of the pan thoroughly every couple of minutes with a spatula to prevent scorching. When the potatoes have started to soften and the cream has thickened, spread the potatoes into an even layer.
- Scatter the grated Parmesan over the top and dot the surface with 2 tablespoons of unsalted butter. Transfer the pan to the top rack and bake, uncovered, until the gratin is golden brown and the potatoes are tender when pierced with a knife, about 25 minutes. Let it rest for 10 minutes before serving.
Notes
The salt in the cream plus the Parmesan provided the right amount of seasoning, so I didn’t need to add any extra.