Mushroom Quiche

I cannot say why this is but I had a hankering for quiche, which is apparently very much ut of vogue because I had trouble finding a recipe for one in any of my more recent cookbooks--including a French one that was published this year--but much as I suspected, I very much enjoyed this. I put it in a deeper tart pan, which the crust recipe worked finr for, and doubled the filling. For the crust 1 1/4 cups flour 1 teaspoon sugar 1/2 teaspoon salt 6 tablespoons very cold (or frozen) unsalted butter, cut into bits, plus more as needed 1 large egg 1 teaspoon ice water For the filling 1 1/2 tablespoons unsalted butter 1 small onion, finely chopped Salt Freshly ground black pepper 8 to 12 ounces mushrooms, trimmed, wiped clean with a damp paper towel and cut into 1/4-inch-thick slices 3 tablespoons white wine or white vermouth (optional) 3 tablespoons finely minced fresh herbs, such as parsley, thyme, rosemary and/or basil 1/4 cup grated Gruyère, Swiss or sharp white cheddar 3/4 cup heavy cream or 1/2 and 1/2 2 large eggs 2 scallions, white and light-green parts only, thinly sliced (optional) Directions For the crust: Combine the flour, sugar and salt in a food processor and whir a few times to blend. Scatter the bits of butter over the flour and pulse several times, to form a coarse, crumbly mixture. Beat the egg with the ice water and pour it into the bowl in three additions, whirring after each one. (Don’t overdo it; the dough shouldn’t form a ball or ride on the blade.) You should have a moist, malleable dough that holds together when pinched. Turn the dough out onto a work surface, gather it into a ball (if the dough doesn’t come together easily, push it, a few spoonfuls at a time, under the heel of your hand or knead it lightly) and flatten it into a disk. Use butter to grease your tart pan — even though the pan may be nonstick. Roll out the dough between sheets of parchment or wax paper. Lift the paper often (so that it doesn’t roll into the dough) and turn the dough over so that you’re rolling on both sides. The rolled-out dough should be about 3 inches larger than the bottom of your pan. Transfer the dough to the tart pan, easing it into the pan without stretching it. (What you stretch now will shrink in the oven later.) Press the dough against the bottom and up the sides of the pan. If you would like to reinforce the sides of the crust, you can fold some dough over, so that you have a double thickness around the border. Use the back of a table knife to trim the dough even with the top of the pan. Prick the base of the crust in several places with the tines of a fork. Refrigerate or freeze the dough in its pan for at least 1 hour before baking. Preheat the oven to 400 degrees. Press a piece of lightly buttered aluminum foil against the dough's surface and fill with dried rice, dried beans or pie weights. Place the tart pan on a baking sheet lined with parchment paper or a silicone liner. To partially bake the crust, bake (middle rack) for 20 minutes, then very carefully remove the foil (with its weights). Return the bare crust to the oven; bake for 3 to 5 minutes. Transfer the baking sheet to a cooling rack and allow the crust to come to room temperature before you fill it. For the filling: Melt the butter in a large skillet, preferably one that’s nonstick, over medium-low heat. Toss in the chopped onion. Season lightly with salt and pepper; cook for about 2 minutes, stirring, until translucent. Add the mushrooms (to taste), season again lightly with salt and pepper. Increase the heat to high; cook for 5 to 8 minutes, stirring, until the mushrooms are softened and browned here and there. At first, the mushrooms will sop up all the liquid in the pan, then they’ll exude it, then take it up again. Add the wine or vermouth, if using; bring to a boil and cook until it evaporates. Sprinkle the onion-mushroom mixture with 1 tablespoon of the minced herbs, cook 30 seconds more, and then transfer to a bowl to cool for at least 15 minutes. When you’re ready to bake the quiche, preheat the oven to 350 degrees. Put the partially baked crust or chilled tart shell on a baking sheet lined with parchment paper or a silicone liner. Sprinkle half the grated cheese evenly over the bottom of the crust and top with the remaining herbs. Spoon over the onion-mushroom mixture, avoiding any liquid that may have accumulated in the bowl. Lightly whisk together the heavy cream and eggs in a large liquid measuring cup just until well blended, then season lightly with salt and pepper. Pour over the cheese and mushrooms in the crust, then scatter the sliced scallions evenly over the top, if you’re using them, and the remaining cheese. Carefully slide the baking sheet into the oven and bake (middle rack) for 30 to 35 minutes, or until the custard is uniformly puffed (wait for the center to puff), lightly golden and set. Transfer the quiche to a rack and cool until it’s only just warm or until it reaches room temperature before serving.