Tuesday, December 7, 2010

Onion Tart with Gruyère--A Guilty Pleasure


Among all the ingredients that one can imagine to make tarts with, onions or mushrooms seem most appropriate for this season. I often bake tarts using seasonal vegetables, but when the weather is cold like this, an onion tart often comes first to my mind. And I really mean a tart not a quiche.

Wherein does the difference lie? First of fall, the crust. A quiche is most often made on a puff pastry crust, while a tart is made on a short pastry crust. Second, how many eggs are used to make the filling. A typical quiche uses a lot of them and, in a quiche, eggs often dominate the taste of other ingredients. But when you make a tart, you can almost do without the eggs. Once I clarified that distinction for myself, I realized that I belonged among the tart, not quiche, lovers. I ate many quiches when I lived in Switzerland, but ever since I tried tarts that are made of pâte sablée or shortcrust, I fell for them deeply.

Recently, I have been experimenting with different tart crusts, and some of them turned out to be very interesting. I will eventually share some of these results. The crust I used today, however, is the most classical and pure, and all the character of the tart is in its rich onion topping.

I got the basic recipe for this tart from my French friend. She made her tart using pâte sablée and did not put any eggs in the onion mixture, which got me very intrigued. The richness of the filling was coming from the heavy whipping cream and cheese. That tart was delicious, although the presentation suffered a bit from the absence of eggs, which would help to lift and tie all the ingredients together. For that reason in my version of that tart I use one egg, which is barely detectable, but makes the topping look smooth and creamy.

Another secret which makes it exceptionally good is the cheese. Nothing can replace Gruyère with its sharp taste and strong flavor. The combination of the sweet onion and Gruyère makes this tart whole. I like to add a little bit of fresh thyme to the topping, but I did not have it handy this time. I suggest to use fresh thyme as it has a milder taste than when it is dry. There is not really any way to make this tart to be a diet meal, but since I already used an egg I decided to replace the heavy whipping cream with the regular table cream to cut down on a few calories, but even with that little replacement, this is not a light dish. But, after all, what is wrong with offering yourself a piece of comfort food with a glass of wine and a bowl of salad on a cold December day?


Onion Tart with Gruyère

The crust (for a 10" baking pan)

Ingredients:
2 cups of flour,
1 stick butter,
3 tbsp shortening,
1 tsp salt,
3-4 tbsp ice cold water.

Preparation:
1. Put all the ingredients in a large bowl and working with your fingers create a mixture that resembles breadcrumbs.
2. Add cold water at the end and stir the mixture until it starts to stick together.
3. Collect the dough until it forms a smooth ball.
4. Wrap the dough in a plastic foil and chill in a refrigerator for a minimum of 30 minutes.
5. Take the dough out and put it on a work surface dusted slightly with flour.
6. Sprinkle a rolling pin with flour and use it to roll the dough to the size of the pan, plus the height of the edges.
7. Preheat the oven to 375F and bake the crust for about 15 minutes, or until the bottom is slightly gold.

Onion topping:

Ingredients:
3-4 medium, regular (not sweet) onions,
1 large egg or 2 smaller eggs,
1 cup grated Gruyère cheese,
1/2 cup table cream (if you are not scared of calories you can use heavy whipping cream),
1 tsp salt,
freshly ground pepper,
1 tsp fresh thyme,
3 tbsp olive oil.

Preparation:
1. Peel the onion and cut it in half and into thin slices (half-moons).
2. Heat the oil and fry onion for about 5 minutes, until it becomes transparent. Cool it down.
3. Mix together egg, salt, and cream and pour the mix over the onion.
4. Add Gruyère and thyme. Mix gently and pour over the pre-baked crust.
5. Bake for another 40-45 minutes until the top becomes gold.
Serve with green salads.