What parts of French Onion soup do you love the most? If you’re like me, you probably enjoy the caramelized onions – a pungent mix of sweet and savory in a way you didn’t realize onions could be. Then there’s the melty, bubbly cheese, nutty and salty in perfect balance. If you’re also like me, the broth isn’t necessarily your thing; often over salted and flat. That’s not to say I’ve never had bombastic, knock your socks off soup. I do think, however, that this tart solves my dilemma. Plenty of onions, a kick from some great Parmesan cheese, and no broth.
Knowing the week looked to be busy, I caramelized a big batch of onions over the weekend. Over the weekend, I can let onions slowly cook into perfection for 30 or 40 minutes and not be too concerned. On a weeknight, that luxury is gone. When it came to the crust, I took a leap of faith — my house is out of plain all purpose flour. My house has been out of plain all purpose flour for a few weeks. I’m apparently bad a remembering the basics at the grocery store.
I tested out using a 100% whole wheat crust, using whole wheat pastry flour. To help with some of that too-healthy taste the often comes with whole wheat flour, I added an extra tablespoon of butter. (That might have been weeknight laziness, I’m not scientifically sure). The end result: move over white flour crust, whole wheat is giving you a run for it’s money.
Serve this tart with a green salad and balsamic vinaigrette. For an extra kick, so fresh rosemary in the crust might be nice.
Caramelized Onion Tart
Onion Tart Filling, adapted from Smitten Kitchen
- 4-7 medium or small onions, sliced into half moons
- 2 tablespoons of olive oil
- 1 teaspoon of sugar
- Salt and pepper to taste
- 1 egg, whisked
- 1/2 cup of milk
- 1 cup shredded parmesan cheese
In a saute pan over medium heat, add the olive oil and onions. Allow the onions to cook down and caramelize, adding the sugar and then the salt to taste. My preferred method of caramelizing onions is to leave them at medium low heat for 30-40 minutes, stirring occasionally while I go about other chores around the house. To do this, make sure your heat is truly at medium low.
Once caramelize, allow the onions to cool by setting aside and storing in the fridge. The onions can be made ahead of time and use day of.
Prep the tart shell (see directions below)
Once the tart pan has been par baked, combine the egg and milk. Whisk together. Mix in the onions, then the cheese. Add the onion custard mixture to the tart shell and bake in a 400 degree oven for about 30 minutes. Use the broiler at the very end if the top hasn’t gotten crisp enough to your liking.
Enjoy with a green salad.
Whole Wheat Tart Shell:
- 1 and 1/4 cups whole wheat pastry flour
- 8 tablespoons of cold butter, cut into squares
- pinch of salt
In a stand mixer fitted with a paddle attachment, combine all the ingredients until a homogenous dough forms. Press the dough into a 9 inch tart shell. Freeze for at least one hour or at most one month. When ready to bake, prick the shell about 10 times with the prongs of a fork. Bake the shell in a 350 degree oven for 7 minutes. Use a spatula to press down any dough that is puffy. Bake for an additional 15 minutes.