While raw onions have a “sting” when you bite into them, baked onions are tender and sweet. Raw onions frequently make me cry, but this onion tart definitely made me smile. Apparently, when you allow raw, biting onions to cook over low heat for a while, they will do an about-face and become soft and sweet, and totally irresistible.
This recipe does not call for a deep caramelization of the onions. They are cooked just enough to reach a beautiful, golden hue. They are then complemented by gruyere cheese, creme fraiche, milk, and thyme, and enveloped by a light, buttery and flaky crust. The result is pure, awesome, homemade comfort food.
Just to note— I doubled the crust, as I always do, and found I needed it when pressing it into the tart pan. I wonder why such small amounts work perfectly for the experts, but not for “home” cooks such as ourselves?
This is an elegant tart that I will be making for one of the upcoming holidays. It will perfectly accompany any main dish, or make a perfect main dish itself.
This recipe is courtesy of Vegetable Literacy by Deborah Madison and will serve 4 as an entree or 6-8 as a side dish or appetizer. I would make two, because as soon as you serve it, there will be nothing remaining but crumbs!
Ingredients for A Fragrant Onion Tart
The filling:
1 1/2 pound onions, preferably white, (about 3 medium)
2 slices of bacon (optional) cut crosswise into small pieces
2 tbsp. butter
1 heaping tsp. fresh thyme leaves, or 2 pinches dried
Sea salt
Freshly ground pepper
3 eggs
1 cup creme fraiche or cream
1/2 cup milk
1 cup grated aged Gouda or Gruyere cheese
The Crust:
1 cup plus 2 tbsp. white whole-wheat or spelt flour
1/4 tsp. salt
6 tbsp. butter, cut into small bits
3 tbsp. ice water or more, if needed
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 them to reduce their sting.
Finely dice the onions.
If you are using 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 1/2 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 be cooked off and they will begin to color. They needn’t be caramelized, but just take on a faint golden hue.
Preheat oven to 400.
When they are 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.
While the onions are cooking, whisk the eggs with the creme fraiche and milk.
Stir in the cooked onions and the cheese.
To make the crust, put the flour and salt in the bowl of a stand mixer fitted with the paddle attachment.
Add the butter and turn mixer to a low speed until the butter has broken into small, pebble-sized 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 are using, wrap it in a plastic bag, and refrigerate.
Roll the dough to fit your chosen tart pan, then drape it into the pan.
Neatly press the dough up the sides of the pan and shape it.
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.
It’s that simple!
