Springtime leeks are the royalty of the onion family and have pride of place in French cuisine, where they appear with vinaigrettes and in quiches, stews and gratins, such as this one. Bursting with flavor, this dish works well as a first course, a main course, or a side, and it can be baked in individual baking dishes or a single large one.
Baked Leeks with Bread Crumbs
6 Tbs. (3 oz./90 g.) unsalted butter
2 Tbs. minced shallots
6-8 leeks, about 3 lb. (1.5 kg.) total, white and pale green parts, chopped
Salt and freshly ground white pepper
2 cups (16 fl. oz./500 ml.) whole milk, plus more as needed
3 Tbs. all-purpose flour
1/4 tsp. cayenne pepper
1/2 cup (2 oz./60 g.) shredded Gruyere cheese
1/2 cup (1 oz./30 g.) fresh bread crumbs
Preheat the oven to 400°F (200°C).
In a frying pan, melt 2 tablespoons of the butter over medium-high heat. Add the shallots, leeks and 1/2 teaspoon each salt and white pepper. Reduce the heat to medium and cook, stirring often, until the leeks are translucent and very soft, about 15 minutes.
In a small saucepan, warm the 2 cups (16 fl. oz./500 ml.) milk over medium heat until small bubbles appear around the edge of the pan. Cover and remove from the heat.
In a saucepan, melt 3 tablespoons of the butter over medium-high heat. Remove from the heat and whisk in the flour, 1/2 teaspoon salt, 1/4 teaspoon white pepper, and the cayenne. Return the pan to medium-low heat and cook, stirring often, for 2 minutes. Slowly whisk in the hot milk and simmer, stirring, until the sauce thickens, about 15 minutes. If the sauce is too thin, increase the heat; if it is too thick, whisk in a little more milk. Stir in the leek mixture.
Pour the mixture into a baking or gratin dish. Sprinkle evenly with the cheese and the bread crumbs and dot with the remaining 1 tablespoon butter. Bake until the cheese and bread crumb topping are golden and the gratin is bubbly, 20-30 minutes. Remove from the oven and serve. Serves 6.
Find more seasonal, vegetable-focused dishes in our new cookbook Vegetable of the Day, by Kate McMillan.