Sweet Pastry Dough
1 ¼ cups all-purpose flour
1 ½ tablespoons sugar
¼ teaspoon salt
7 tablespoons cold unsalted butter, cut into bits
1 large egg yolk
½ teaspoon vanilla
½ teaspoon fresh lemon juice
2 ½ tablespoons cold water
4 Florida grapefruit (preferably 2 pink and 2 red), segmented and pith removed
8 oz. mascarpone cheese at room temperature
3 tablespoons finely chopped candied ginger
4 tablespoons confectioners’ sugar
Whisk together flour, sugar, and salt in a large bowl.
Blend together flour and butter with your fingertips or a pastry blender until most of mixture resembles coarse meal with small (roughly pea-size) butter lumps. Beat together yolk, vanilla, lemon juice, and water with a fork and stir into flour with fork until combined well.
Gently knead with floured hands in bowl until a dough forms. Turn dough out onto a floured surface and gently kneaded 4 or 5 times.
Form dough into a ball, then flatten into a disk and chill, wrapped in plastic wrap, at least 1 hour and up to 2 days
Preheat oven to 375°F. Roll out dough with a floured rolling pin into a 13-inch round on a floured surface and fit into 9-10 inch tart pan (if pastry breaks, press together with your fingers). Trim excess dough, leaving a ½-inch overhang, then fold overhang inward and press against side of pan to reinforce edge. Lightly prick bottom of shell all over with a fork. Chill 30 minutes.
Cover shell with parchment and baking beans. Bake for 10-15 minutes until edges appear golden.
Remove weights and bake for another 10-15 minutes until golden-brown. Cool completely.
Fold candied ginger into mascarpone cheese. Spread mixture into cooled pie shell.
Place segmented grapefruit evenly on top of tart.
Sift confectioners’ sugar over tart.