Eat This: Mid-August is primetime for this plum tart

By Gretchen McKay / Pittsburgh Post-Gazette

I’m a happy camper this time of year, and no, not because kids are going back to school.

Mid-August is when Italian plums come to market. To find them piled high in wooden pint baskets at a local market is like winning the lottery.

Slightly tart and a little more egg-shaped than a common plum, “prune plums” develop a rich, sugary-sweet flavor and jammy texture when cooked. That means they’re terrific not just for jam but also in pies, crumbles, cakes and tarts. Plus, since they’re a free stone fruit, the pits come out without any trouble. What cook doesn’t like that?

I use pint after pint of the purple fruit when it’s in season in one of my all-time favorite desserts: The New York Times’ famed plum tart. This year, though, that recipes has some competition from Fine Cooking. Its recipe pairs prune plums tossed in sugar and lemon zest with a lemon shortbread crust that requires no rolling — you simply pat it into the pan.

I made it even more delicious by brushing homemade peach jam on the tart shell before adding the plum filling. The entire dessert disappeared in less than a day, because my husband and I ate it for breakfast and also as a late-night snack.

A ripe plum should smell sweet and fruity, and feel heavy. Don’t worry about the spots of powdery white known as bloom — the fruit secretes it to protect against bugs and bacteria, and it’s actually a sign of freshness. It’s harmless and edible.

Plum tart with lemon shortbread crust

For the filling:

⅓ cup plus ½ tablespoon granulated sugar, divided

1 tablespoon cornstarch

Pinch of kosher salt

¼ teaspoons finely grated lemon zest

14 ripe Italian plums (about 1½ pounds), each pitted and sliced into slender wedges

For the tart shell:

8 tablespoons cold unsalted butter, cut into ½-inch cubes; plus more softened for the pan

1 large egg yolk

2 teaspoons firmly packed, finely grated lemon zest

½ teaspoon pure vanilla extract

1 cup and 3 tablespoons unbleached all-purpose flour; more as needed

¼ cup granulated sugar

Pinch of table salt

2 tablespoons plum or peach preserves

Prepare filling: In a medium bowl, whisk ⅓ cup of the sugar and the cornstarch, kosher salt and lemon zest. Add sliced plums and gently toss with your hands to evenly coat with sugar. Cover the bowl and put in the refrigerator for at least 3 hours or overnight.

Make the tart shell: Lightly butter the bottom and sides of a 9½-inch fluted tart pan with a removable bottom.

Put butter cubes in the freezer and whisk egg yolk, lemon zest and vanilla in a small bowl.

Place flour, sugar and table salt in the bowl of a food processor and pulse a few times to combine. Add butter and pulse until the mixture is crumbly and mealy, about 25 short pulses.

Add the egg yolk mixture and blend, using long pulses, just until it forms a moist, crumbly mass, about 15 3-second pulses. The dough won’t come together on its own, but it should hold together when squeezed.

Transfer dough to the tart pan. Dip the bottom of a flat-bottomed cup measure in flour and use it to press the dough onto the bottom and sides of the pan in an even layer. Start with the sides, which should be ¼ inch thick. Reflour the cup whenever it starts to stick to the dough. Wrap the pan in plastic and refrigerate it for at least 1 hour and up to 1 day.

Blind bake the shell: Position a rack in the lower third of the oven and heat the oven to 375 degrees. Unwrap the tart shell and prick the bottom and sides several times with a fork. Spray one side of a piece of parchment or foil with cooking spray.

Line the shell with the sprayed side down and fill the lined shell with pie weights or dry beans. Set the tart pan on a baking sheet and bake for 20 minutes. Carefully remove the liner and pie weights. Should any dough stick to the liner, peel it off and patch it back into the shell.

Reduce heat to 350 degrees and continue baking until the sides and bottom of the shell are golden brown and dry, 10-15 minutes more. Cool on a rack for about 20 minutes.

Finish the tart: Drain plums in a sieve or colander set over a medium bowl for a few minutes.

Pour juice into a small saucepan and bring to a simmer over medium heat. Reduce heat to low and simmer, stirring occasionally, until very thick, about 3 minutes. Scrape into a small bowl and let cool for about 10 minutes.

Meanwhile, melt preserves in the saucepan over medium-low heat or microwave in a small bowl until syrupy. Pour preserves into tart shell and evenly brush them over the bottom and sides. With a rubber spatula, spread the plum juice over the preserves on the bottom of the shell.

Starting at the edge of the shell, arrange plum slices cut side down and tightly overlapping in concentric circles. If you have more slices, keep tucking them in wherever they fit. You can also pile a few in the center.

Sprinkle the remaining ½ tablespoon sugar over the plums.

Bake the tart directly on the oven rack until the plums are tender when poked with a paring knife and caramelized along their edges (a few tips may even blacken). The crust should be a deep golden brown, and any juices should be syrupy and bubbly, 40-50 minutes. After you remove the tart from the oven, moisten the plums by dipping a pastry brush into the juices and brushing any surfaces that look dry.

Cool the tart in its pan on a rack for at least 2 hours before unmolding and slicing with a very sharp knife.

— Adapted from finecooking.com