Tomato Onion Tart

You can tell that summer is winding down when butternut and acorn squash start showing up on the tables at the farmers’ market. I am craving autumn and the cooking that comes along with cooler weather and yet I can never seem to be able to let go of fresh tomatoes. Happily there are still plenty of tomatoes piled next to the fall squashes and I plan on eating them day after day until they are gone.

Maybe if you live in NYC you have visited Once Upon A Tart. I love their cookbook and wish they had a shop in my neighborhood. The inspiration for this tart came from their book and the crust recipe is theirs. The semolina gives it just the right amount of crunch. I’m glad I have another crust tucked away in the freezer.

Savory Crust (from Once Upon A Tart) Makes enough for 2-9″ crusts

2 1/2 cups unbleached all-purpose flour
3 tablespoons semolina flour
1 teaspoon salt
12 tablespoons (1 1/2 sticks or 6 ounces) cold unsalted butter, cut into 1/4-inch cubes
3 tablespoons cold solid vegetable shortening
a glass of ice water

Put flours and salt in the bowl of a food processor fitted with a metal blade and pulse to combine.

Add the butter and shortening and pulse several time until the mixture resembles coarse crumbs with some butter chunks still visible.

Remove the blade from the food processor and dump the dough into a large bowl. Sprinkle 4 tablespoons of ice water evenly over the dough, then use your hands or a wooden spoon to bring the dough together to form a ball. The dough should be just past crumbly, but holding together. Add more water as needed, a tablespoon at a time, if necessary to get the dough to come together.

Cut the dough in half, shape each half into a disk, and wrap each disk in plastic wrap. Refrigerate at least 30 minutes before rolling out.

Preheat the oven to 400 degrees F. Roll out dough to 1/4 inch thickness, fit it into your tart pan, and trim the edges. Chill 30 minutes. Prick the bottom of the tart with the tines of a fork, line the tart with parchment or foil and fill with pie weights or dried beans.

Place the tart shell on the center rack of the oven and bake for 10 minutes. Remove the paper and weights from the pan and return the tart crust to the oven. Bake another 5-10 minutes for a par-baked shell (crust is golden brown and no doughy areas remain), or bake for 10-20 minutes for fully-baked tart shell (golden brown all over). Cool on a wire rack.

Filling

3 large tomatoes, sliced
2 large onions, thinly sliced
1 tablespoon fresh thyme leaves
2 tablespoons olive oil
Salt and freshly ground pepper
2 eggs
1/4 cup heavy cream
4 tablespoons grated Parmigiano-Reggiano

Heat olive oil in large skillet over medium low heat. Add sliced onions, season with salt, pepper and thyme and saute until onions are soft and slightly caramelized, about 20 minutes. Remove from heat and let cool.

Place the tomato slices in a colander and place in sink. Let the tomatoes sit for 15 minutes to drain off liquid. Spread the cooled onions over the bottom of the tart shell. I used a rectangular tart pan but the recipe works in a 9″ round pan too.

Lay the tomato slices in overlapping rows (or concentric circles if using round pan) over the onions. Sprinkle with grated cheese. Mix eggs and cream together, season with salt and pepper and pour over tomatoes.

Place the tart in the oven and bake for 45 minutes to 1 hour or until custard is set. Remove from oven and let cool on a rack. Allow the tart to cool slightly and then remove from ring and place on a serving dish. Serve warm or at room temperature.