Blackberry Basil Tart

Ingredients
Serves 6
2 cups sour cream
3/4 cup plus 3 tablespoons sugar
1/2 vanilla bean, halved lengthwise
Cornmeal Shortbread Dough
2 cups blackberries (about 1 pint)
1/4 cup loosely packed fresh basil leaves, plus sprigs for garnish
1/4 teaspoon ground cinnamon
Directions
1.Stir together sour cream and 3/4 cup sugar. Scrape in vanilla bean seeds; stir to combine. Discard pod. Refrigerate filling, covered, until firm, about 3 hours or up to 2 days, before using.
2.Preheat oven to 375 degrees. Press dough into a 13 3/4-by-4 1/4-by-1-inch oblong tart pan with a removable bottom. Trim edges of dough flush with pan. Refrigerate until firm, about 30 minutes. Bake until golden and crisp, about 18 minutes. Let cool completely on a wire rack.
3.Stir together blackberries, remaining 3 tablespoons sugar, 1 tablespoon water, basil, and cinnamon in a small saucepan over medium heat. Cook, stirring gently, until berries have softened and released their juices and mixture is warmed through, about 2 minutes.
4.Spoon sour cream filling into tart shell. Top with the berry mixture. Garnish with basil sprigs.

Cornmeal Shortbread Dough
Ingredients
Makes enough for 1 tart
1 1/4 cups all-purpose flour
3 tablespoons fine yellow cornmeal
1/4 teaspoon salt
1 large egg yolk
1 1/2 tablespoons heavy cream
1/2 teaspoon pure vanilla extract
6 tablespoons unsalted butter, softened
3 tablespoons sugar
1 tablespoon finely grated orange zest
Directions
1.Whisk together flour, cornmeal, and salt in a large bowl; set aside. Whisk together yolk, cream, and vanilla in a small bowl; set aside.
2.Put butter and sugar in the bowl of an electric mixer fitted with the paddle attachment. Mix on medium speed until pale and fluffy, about 2 minutes. Mix in yolk mixture and orange zest until combined. Mix in flour mixture until just combined. Shape dough into a disk; wrap in plastic. Refrigerate until cold, about 30 minutes or up to 1 day, before using.