Long, stalky green leeks never seem to get the attention they deserve here in the States. In Europe, they are a staple ingredient used in everything from basic stocks and wintery braises to baked quiches and roasts. These giant scallions benefit from low, slow cooking methods that soften their tough, fibrous leaves, imparting a mellow complexity that enhances the other flavors in a dish. Leeks can be found at the market year-round in our neck of the woods, but Chef Mark Peel of Bombo says they are best during the colder months when the young stalks are still sweet and tender.
At home, Peel makes his rustic leek tart using a pre-baked puff pastry crust. The leeks are thinly sliced across the grain and stewed in a generous amount of butter, garlic, sage and thyme. He then sets the leeks in a rich custard base of crème fraîche mixed with egg yolk and a sprinkling of herbed garlic bread crumbs.
Yield: Makes one 9-inch tart
A 9-inch sheet commercial puff pastry, pre-baked
2 tbsps unsalted butter
1 lb leeks, light part only
1 tsp kosher salt
1 fat garlic clove, cut in half and sliced thinly
2 fresh sage leaves, chopped
½ tsp fresh thyme leaves
½ cup heavy cream
½ cup crème fraîche
1 large egg yolk, beaten
¼ tsp freshly ground black pepper
½ cup herbed garlic bread crumbs
Clean the leeks: Cut away the root ends and slice the leeks lengthwise. Transfer them to a large bowl. Soak in cold water and swish the sliced leeks around to loosen any caked mud or sand. Transfer the leeks to a strainer and drain the water from the bowl. Rinse the bowl out and fill again with cold water. Repeat this process as needed until no more sand remains. Then rinse the sliced leeks and drain on paper towels.
Sauté the leeks: Heat the butter in a large, heavy skillet over medium-low heat and add the leeks, salt, garlic, sage and thyme. Cook gently, covered, until the vegetables are very tender, about 20 minutes. Do not brown. If the leeks begin to stick to the pan and color, transfer them to a new pan. Add a tablespoon of water and the heavy cream. Continue to cook, uncovered, until almost all of the cream is absorbed, about 10 minutes. Remove from heat and stir in the pepper.
Preheat the oven to 350ºF.
Prepare the tart: Beat together the crème fraîche and egg yolk, and spread over the mixture over the pre-baked pie crust. Spoon in the leeks, then gently arrange them in a layer. Sprinkle the bread crumbs over the surface in an even layer.
Bake the tart: Transfer the tart to the oven and bake for 30 minutes, until a crust has formed over the top. The surface should feel slightly resistant to the touch. Remove the tart from the oven and allow to rest for at least 10 minutes before serving.