This Blueberry & Nectarine Open-Face Tart is simplicity itself: crust, jam, and fruit. It’s also completely delicious. Over the years, we’ve tried many methods for making a perfect piecrust, and this one—mixing the ingredients by hand in a single bowl—produces the best results with the least fuss.
1-1/4 cups all-purpose flour, plus more for work surface
2 tablespoons plus 1 tablespoon granulated sugar
1/2 teaspoon kosher or sea salt
8 tablespoons chilled unsalted butter, cut into small cubes
3–4 tablespoons ice water
1 large egg white
First make the crust: In a medium-size bowl, whisk together the flour, 2 tablespoons of sugar, and salt until well combined. Sprinkle the butter cubes on top and use your fingers to work them in. (Rub your thumb against your fingertips, smearing the butter as you do.) Stop when the mixture looks like cornmeal with some pea-sized bits of butter remaining. Sprinkle 3 tablespoons of ice water on top, and stir with a fork until the dough begins to come together. If needed, add 1 tablespoon more of ice water. Turn the dough out onto a lightly floured surface and knead three times.
Gather the dough into a ball; then press it into a disk and wrap it in plastic wrap. Refrigerate at least 30 minutes.
3 large nectarines, unpeeled and sliced into ½-inch-thick wedges
1 tablespoon maple syrup
1 teaspoon cornstarch
1/4 teaspoon ground cardamom
1/4 cup seedless raspberry jam
1/2 cup high-bush blueberries (¼ cup if using small wild berries)
Garnish: Crème fraîche or whipped cream (optional)
While you’re waiting for the dough to chill, prepare the fruit: Toss the nectarines with the maple syrup, cornstarch, and cardamom. Set aside.
Preheat your oven to 400° and set a rack to the second-from-bottom position. Line a baking sheet with parchment paper and set aside. Remove the dough from the refrigerator and roll out on a lightly floured counter to a circle about 16 inches wide and 1/8 inch thick. Transfer to the lined baking sheet. Spread the raspberry jam over it, leaving a 2-1/2-inch border all around. Arrange the nectarine slices in overlapping circles atop the jam, leaving an empty 3-inch well in the center (the blueberries will go here later).
Fold the sides of the dough up and over the edge of the nectarines, letting the dough drape over itself at each fold. Brush the edges with the egg white and sprinkle all over with the remaining tablespoon of sugar. Bake 10 minutes; then lower the temperature to 375° and bake 20 minutes more.
Pour the blueberries into the empty well in the center, mounding them slightly; then bake until the crust is nicely browned, another 7 to 10 minutes. Let cool at least 20 minutes before serving; let cool completely if you plan to pack the tart for a picnic. To serve, spoon the crème fraîche or whipped cream over the tart if you like.