Sunday, August 7, 2016

Lemon  Blueberry Buttermilk Tart

Blueberry season is here. What to make? Another blueberry crumb cake or muffin? A juicy blueberry pie? As wonderful as these desserts are, sometimes it’s nice to try something new. Sooooo, here’s my contribution: a riff on a Southern American classic, the buttermilk pie. A variation on a recipe in my book Flavorful

this buttermilk tart has a filling that is very similar to cheesecake in flavor, though its texture is much less dense. I added buttermilk to the tart dough, too, which makes the resulting crust very tender and slightly tangy. Serve this dessert at room temperature, not chilled, and preferably on the day you make it. That shouldn’t be a problem.

Lemon Blueberry Buttermilk Tart

Makes one 9 1/2-inch tart, serving 6 to 8

Tart Dough:
1 ¼ cups (166 g) all-purpose flour
1 teaspoon (4 g) granulated sugar
¼ teaspoon (1.6 g) salt
8 tablespoons (113 g) unsalted butter, cut into ½-inch cubes and frozen for 20 minutes
3 tablespoons (45 g) cold buttermilk

Eggwash and sugar topping (for optional garnish):
1 large egg
1 teaspoon water
Granulated sugar for sprinkling on top

Lemon Buttermilk Filling:
¾ cup (150 g) granulated sugar
1 ½ tablespoons (12 g) all-purpose flour
3 large eggs
1 large egg yolk
5 tablespoons (70 g) unsalted butter, melted and cooled
¾ cup (181 g) buttermilk
¾ teaspoon (3 g) vanilla extract
1 teaspoon (2 g) finely grated lemon zest
2 tablespoons (30 g) freshly squeezed lemon juice

Blueberry Topping:
2 2/3 cups blueberries, divided
2 tablespoons (25 g) granulated sugar

Make the tart dough:
1. Place the flours, sugar and salt in the bowl of a food processor and pulse few times to combine. Add the butter pieces and toss lightly with a spoon to coat them with flour. Blend the fat and flour with about five 1-second pulses or until the mixture is the texture of coarse meal with some of the butter pieces the size of peas. Sprinkle the buttermilk over the flour mixture and process continuously until the dough begins to clump together. Do not over-process; the dough should not form a ball. Turn the dough out onto a work surface and shape it into a thick 4-inch wide disc. Wrap the dough in plastic wrap and chill until firm enough to roll, about 30 minutes.
2. Place unwrapped dough on a work surface that has been lightly dusted with flour. Using a rolling pin, roll the dough out into an 11-inch circle, lifting and rotating the dough often, while dusting the work suface and dough lightly with flour as necessary. Roll the dough up on the rolling pin and unroll it over a 9-inch fluted tart pan with a removable bottom. Gently press the dough onto the bottom and up the sides of the pan. Roll the pin over the top of the pan to trim off the excess dough. Lightly prick the bottom of the dough with a fork at 1-inch intervals. Refrigerate the dough in the pan for 20 minutes to firm up the dough. (If you like, roll out the dough scraps and, using a 1-inch heart or flower-shaped aspic cutter, cut out as many shapes as you can, place them on a small plate and refrigerate them along with the tart shell. These shapes can be baked later and used to garnish the tart.)
3. Preheat the oven to 375°F. Right before baking, line the dough with aluminum foil or parchment paper and cover with pie weights or dried beans. Place the tart pan on a baking sheet and bake for 15 minutes. Carefully lift the foil (along with the weights) out of the tart pan and bake the crust for 8 to 10 minutes longer, until it just begins to turn golden brown in spots along the edge. Transfer the tart pan to a wire rack and cool while you make the filling. (If you’ve made the pastry hearts or flowers, prepare the eggwash by whisking together the egg and water until smooth. Brush the eggwash onto the small shapes, sprinkle them with sugar, and bake them at 375°F for about 7 minutes, until they are just beginning to turn golden. Cool and set aside.) Reduce the oven temperature to 300°F.

Make the filling:
4. In a medium bowl, whisk together the sugar and flour. Add the eggs and yolk and whisk until smooth. Whisk in the melted butter, buttermilk, vanilla, lemon zest and lemon juice.
5. Place the tart pan on a baking sheet and carefully pour the filling into the tart shell (it will fill the shell). Bake the tart for 50 to 60 minutes, until the filling is just set in the center. Cool the tart on a wire rack.

Make the topping:
6. In a small saucepan, comebine 1 cup of the blueberries with the sugar. Place over low heat and cook, stirring occasionally, until the berries release their juice and become saucy. Place the berries and sauce in a fine-mesh strainer and set it over a bowl. Strain the berries, pressing down on them to extract as much liquid as possible. Discard the strained berries. Toss the remaining 1 2/3 cups berries in the blueberry sauce.
7. Spoon the saucy berries over the cooled tart, spreading them evenly.

Garnish the tart:
8. Garnish the whole tart with the pastry shapes.