Weigh or lightly spoon flours into dry measuring cups; level with a knife. Place flours and 1/4 teaspoon salt in a food processor; pulse to combine. Add butter; pulse 6 times or until mixture resembles coarse meal. Add 1/4 cup water and vodka; pulse 6 times or until dough comes together. Turn dough out onto a lightly floured surface; gently knead 1 to 2 times. Divide dough into 12 equal portions; shape each portion into a ball and press flat. Roll each dough portion into a 4 1/2-inch circle. Arrange dough circles on a baking sheet lined with plastic wrap; cover and chill 1 hour or until firm.
Preheat oven to 375°F with oven rack in lower middle position.
Unwrap dough circles; fit 6 circles into 6 (4-inch) tart pans. Using a 1 1/4-inch star-shaped cutter, cut a star from the center of each of the remaining 6 dough circles. Refrigerate tart shells and lids until ready to use; refrigerate stars, if using.
Combine remaining 1/4 teaspoon salt, 5 tablespoons sugar, and cornstarch in a large bowl. Add cherries and lemon juice; toss. Spoon about 1/2 cup cherry mixture into each shell; top with dough lids, pressing edges to seal. Brush with egg white; sprinkle with remaining 2 teaspoons sugar. Arrange tartlets on a foil-lined baking sheet; bake at 375°F for 35 to 40 minutes or until golden and bubbly. Cool 10 minutes. Remove tartlets from pans; cool completely.