Leek Gratin

This creamy leek gratin from Chef Brett is everything we love about cold-weather cooking—simple, cozy, and full of flavor. With tender leeks and a crisp, golden topping, it’s the perfect side dish for a holiday gathering, especially as the cooler days start to roll in. There’s nothing better than a warm, comforting dish like this.

Project Angel Heart Registered Dietitian Zachary Hedden notes that this dish delivers rich flavor alongside a variety of nutrients that support digestion, heart health, and bone strength. Leeks provide fiber, vitamin K, folate, and antioxidants that support digestion, heart health, and reduced inflammation. Olive oil contributes heart-healthy monounsaturated fats, while garlic and thyme offer additional antioxidant and anti-inflammatory compounds. Using gruyère or parmesan adds protein and calcium to support bone health, and the breadcrumb topping brings great texture and flavor. 

Serves 4-6 people

  • 4 large leeks, white and light green parts only
  • Salt
  • 2 tablespoons butter
  • 1 tablespoon olive oil
  • 2 garlic cloves, minced
  • 1/4 teaspoon thyme leaves (fresh or dried)
  • Freshly cracked black pepper, to taste
  • 1/4 cup white wine (optional)
  • 1/2 cup heavy cream
  • 1/2 cup grated gruyère or parmesan (or a mix)
  • 1–2 tablespoons chives, finely sliced

For the Bread Crumb Topping:

  • 3/4 cup fresh breadcrumbs (or Panko)
  • 2 tablespoons butter, melted
  • 2 tablespoons grated parmesan
  • 1 tablespoon chopped parsley
  • Pinch of salt

Cut leeks in half lengthwise, then into 2-inch pieces. Rinse thoroughly under running water to remove grit. Bring a large pot of salted water to a boil and blanch leeks for 3 minutes. Drain well and pat dry.

Heat butter and olive oil in a skillet over medium heat. Add garlic and cook until fragrant (about 30 seconds). Add leeks, thyme, salt, and pepper; sauté for 3–4 minutes. Add white wine and cook until mostly evaporated, if using. Add heavy cream, bring to a gentle simmer, and cook for 2 minutes to thicken slightly.

Pour the leek mixture into a small gratin or baking dish. Sprinkle gruyère or parmesan (or a mix) over the top.

For the breadcrumb topping, mix the breadcrumbs with melted butter, parmesan, parsley, and salt in a small bowl, then scatter evenly over the leek mixture.

Bake at 400°F for 15–18 minutes, or until bubbling and the top is golden and crisp. Broil for 1–2 minutes at the end for extra color, if desired. Top with chives and serve.

Enjoy!