Caramelized Onion Quiche
 
 
Winter market onions are simmered slowly until caramelized then layered with Gruyere cheese and covered with a thick custard all held together with an easy flaky crust.
Author:
Ingredients
For the caramelized onions:
  • 2 large onions (about a pound)
  • 2 Tablespoons butter
For the crust:
  • 1 cup flour
  • 1 stick unsalted butter (1 stick), very cold and cut into small cubes or grated
  • ½ teaspoon sea salt
  • 1 egg, beaten
  • 3 Tablespoons ice water
For the custard:
  • 1 cup heavy cream
  • ½ cup whole milk
  • 3 large eggs
  • ½ teaspoon sea salt
  • pinch nutmeg
  • 1 overflowing cup of grated Gruyere cheese*
Instructions
  1. Preheat the oven to 375 degrees.
For the caramelized onions:
  1. Melt the butter over medium low heat in the bottom of a large fry pan or stock pot. Add onions. Lower heat until onions are just slowly sizzling. Keep an eye out and stir every 7-10 minutes, more frequently as they start to brown. The entire process will likely take about 30 minutes until they turn medium brown. Set aside to coll.
  2. While the onions slowly caramelize, prepare the crust.
For the pie crust:
  1. Butter a 9-inch pie or tart dish.
  2. Place flour and salt into the bowl of a food processor. Blitz for a second to combine.
  3. Add butter cubes and pulse until butter is cut into pea-sized bits.
  4. Add egg, pulse 2 times
  5. Add cold water and blitz just until the dough starts to come together. The dough will likely look more like a pile of crumbs than a dough. Carefully squeeze a bit of the dough in your hand. If it holds its shape, it is ready. If you squeeze and still have a handful of crumbs, add a little more water.
  6. Pull out about a foot-long piece of plastic wrap onto a pastry board or a nonstick silicone pastry mat. Carefully dump crumbly dough onto the plastic wrap and knead into a ball. Wrap in the plastic wrap and put into the fridge to chill for at least 30 minutes.
  7. Roll dough out into about a 12-inch circle.** Drape dough over the rolling pin and gently transfer over and into the buttered pie plate or tart pan. Press down in the center, then gently into the sides of the pan. Roll the dough over the top of the pan to press off and remove any excess dough. (I sometimes need to take excess dough and patch in on sides that don't have enough dough either because I didn't roll into a perfect circle or I didn't transfer evenly into the pan. That works just fine!)
  8. Place the pie pan with crust into the freezer while you prepare the custard.
For the custard:
  1. In a medium bowl or large glass measuring cup, whisk together all the ingredients until combined.
To assemble the quiche:
  1. Place the cooled onions into the bottom of the crust. Add the cheese. Pour over the custard until onions and cheese are evenly coated.
  2. Bake for 35-40 minutes until quiche is browned and center is firm in the center.
  3. Cool for at least 5 minutes before serving.
Notes
*Gruyere cheese is sold in the specialty cheese section of the grocery and I am never without a wedge during the winter months. It has a slightly salty, nutty flavor and is the only cheese I use for any dish that calls for melted cheese. It adds incredible flavor and melds into a dish without being clumpy or sticky. I find a fairly inexpensive but good version at Trader Joe's and shred using the shredding blade of my food processor.
**To roll out dough, press from the center and roll outward. Rotate the dough about 2 inches after every swipe of the rolling pin to create an even circle.
Recipe by FamilyandForks at https://www.familyandforks.com/caramelized-onion-quiche/