SERVINGS
6-8
INGREDIENTS
HOW TO MAKE IT
Step 1/4
Preheat the oven to 375°F.
Step 2/4
Bring a large cocotte of water to a boil and fill a bowl with ice and water to make an ice-water bath. Add the leeks to the boiling water and cook until bright green and slightly softened, 2 to 3 minutes. Shock the leeks in the ice-water bath to prevent further cooking. Drain and set aside.
Step 3/4
In a 4-quart cast-iron cocotte, combine the cream, butter, garlic, thyme, and 3⁄4 cup whole hazelnuts. Bring to a boil, then reduce the heat to low and simmer for 30 minutes for the flavors to combine. Remove thyme sprigs, then transfer to a blender and blend until smooth. Fold in the cheese. Season with salt and pepper and add a little lemon juice, if needed.
Step 4/4
Place the leeks in a large oval cast-iron roasting pan and cover with the cream mixture. Sprinkle the panko over the top and bake for 30 to 40 minutes, until golden brown and bubbly. Chop the remaining hazelnuts then sprinkle over gratin along with chives and serve.