French Recipes: Caramelized Onion and Leek Tart

The French are culinary masters at both the sweet and savory. Sometimes French recipes can even blur the lines of each with the amount of butter used. Take crêpes, for instance. Whenever I can manage to get into the always-popular crêpe spot Breizh Café, I’m conflicted about whether to order a warm galette filled with gently roasted duck and a creamy goat cheese, or just go straight to a sweet crêpe oozing with salted butter caramel and a scoop of cool vanilla ice cream. Of course, this dilemma is easily solved by ordering both.
I always face a similar problem when I stop by the boulangerie for a simple baguette. Opening the door, I’m confronted with the wonderful mingling of smells from flaky butter and warm chocolate, so naturally I walk out with a pain au chocolat in one hand and my nearly forgotten baguette in the other. 

And then there are the tarts. How can I walk away from a tarte au sucre? Not to mention a fruit tart, lemon tart or chocolate tart? Again, I can’t, but I’ve also been enjoying the sister savory tarts that share a similar flaky, crispy crust. These can also include seasonal vegetables, cheese and a little bacon, which is always a welcome addition.
Given my love for the sweet and the savory, I am once again trying for the best of both worlds with a savory tart, which combines sweet leeks and caramelized red onions. It’s perfect for breakfast, lunch or dinner, paired with a green salad or even a side of prosciutto and melon. 

What makes the tart so delicious is the crust, and while you can absolutely buy a prerolled dough for a fast and easy meal, why not spend a little extra time to make a traditional pâte brisée for a taste of the real deal? And if you want to go the full handmade distance, you can forego the food processor and get your hands in there to mix the dough yourself.

Caramelized Onion and Leek Tart

Serves 6–8.
Pâte Brisée
1½ cups flour (170 grams)
8 tablespoons cold butter, cut into small pieces
¼ teaspoon salt
1 egg
cold water
1. Combine the flour and salt in a food processor.
2. Gradually add the butter in short pulses. It should turn crumbly, like a coarse meal.
3. Blend in the egg.
4. Add water in small amounts, just until the dough combines.
5. Roll into a ball, flatten, cover with plastic wrap and refrigerate for at least an hour. It can also be refrigerated overnight or frozen for up to a month.
6. Preheat the oven to 375°F (190°C). Bring the dough to room temperature and place it on a lightly floured surface. Roll it out and place in a greased 9-inch pie plate or tart pan. Press on the bottom and sides for a smooth surface, and trim and crimp the edges, allowing for some overhang to compensate for shrinkage during baking.
7. Pierce the bottom of the dough with a fork to reduce puffing while cooking. Place parchment paper on top and fill with pie weights or a mixture of rice and beans to further discourage rising while cooking. Bake approximately 15 minutes or until the crust begins to dry and lightly color. Remove the parchment and weights and cook another 10–15 minutes until golden.
8. Remove and cool.
Filling
2 leeks
2 red onions
3 tablespoons butter
4 ounces goat cheese, diced
1 cup cream
2 eggs
olive oil
sugar and balsamic vinegar (if desired)
salt and pepper
1. Slice the onions in half and then lengthwise.
2. Coat the bottom of a heated pan with olive oil and 1 tablespoon of butter, and then add the sliced onions. Stir occasionally but not frequently to allow caramelization to occur. Add salt after about 10 minutes. A dash of sugar or swirl of balsamic vinegar will speed the caramelization process and add to the sweetness. If the onions start to dry out, add a little water. Keep over low heat for up to an hour, until the onions are a rich brown.
3. While the onions cook, wash the leeks and cut off and discard the dark green leaves. Slice lengthwise and then across. Rinse again.
4. Heat 2 tablespoons of butter and sauté the leeks until soft, about 10 minutes.
5. When both items have finished cooking, combine into one pan. Add diced goat cheese and blend. Pour the mix into the tart shell.
6. In a bowl, whisk the cream, eggs and salt and pepper, and then pour the mixture over the onions and leeks.
7. Bake for approximately 20 minutes in the center of the oven, and then transfer to the top for another 10–15 minutes, until the mixture is set and browned and bubbly. Transfer the pan to a rack to let the tart rest and cool before serving.

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