Fragrant Onion Tart
  • pounds onions, preferably whiteabout 3 medium
  • 2slices bacon (optional), cut crosswise into small pieces
  • 2tablespoons butter
  • 1heaping teaspoon fresh thyme leavesor 2 pinches dried
  • sea salt
  • freshly ground pepper
  • 3 eggs
  • ½cup crème fraîche or cream
  • ½cup milk
  • 1 cup grated aged Gouda or Gruyère cheese
  • 1cup plus 2 tablespoons white whole-wheat or spelt flour
  • ¼teaspoon salt
  • 6tablespoons buttercut into small bits
  • 3tablespoons ice wateror more if needed
  1. To make the filling, cut your onions in half, peel them, and if they are strong, put them in a bowl of cold water. It doesn’t take long for that to reduce their sting. When you’re ready, finely dice them. (White onions usually aren’t as strong as yellow ones.)
  2. If you’re using the bacon, fry it until browned and nearly crisp, then scoop it out to drain on a paper towel. Throw out the bacon grease, wipe out the pan, and add the butter. When melted, add the onions, thyme, and ¾ teaspoon salt. Cook over medium heat, stirring occasionally, about 25 minutes in all. At first the onions will be very moist, but after 10 minutes their water will have cooked off and they’ll begin to color. They needn’t be caramelized, but just take on a faint golden hue. When done, let them cool slightly. Taste for salt—they’ll be very sweet, so you might want to add more—and season well with pepper.
  3. While the onions are cooking, whisk the eggs with the crème fraîche and milk. Stir in the cooled cooked onions and the cheese.
  4. To make the crust, put the flour and salt in the bowl of a stand mixer fitted with a paddle attachment. Add the butter and turn mixer to low speed until the butter has broken into small, pebble-size pieces. Drizzle in the ice water until the dough looks clumpy and damp. You’ll use about 3 tablespoons or less if the butter was soft. Form the dough into a disk or a rectangle to correspond to the shape pan you’re using, wrap it in a plastic bag, and refrigerate.
  5. Heat the oven to 400°F.
  6. Roll the dough to fit your chosen tart pan, then drape it in the pan. Neatly press the dough up the sides of the pan and shape it. Set it on a sheet pan. When the oven is ready, pour in the onion mixture, even it out, then bake until the surface is golden and browned in places, 45 to 50 minutes. Let cool to warm before cutting into slices and serving.
Recipe Notes

Reprinted with permission, from Vegetable Literacy by Deborah Madison, copyright © 2013. Published by Ten Speed Press, a division of Random House, Inc.