Fruit Filled Mini Toaster Pastries

Name: Fruit Filled Mini Toaster Pastries
Ingredients: 5 tablespoons cold water; 1 tablespoon apple cider vinegar; 2 cups all-purpose flour, plus more for rolling out the dough; 1 tablespoon granulated sugar; 1/8 teaspoon fine sea salt; 1 1/4 sticks cold unsalted butter, cut into small pieces; 2 cups fresh strawberries, quartered or 2 cups raspberriesor 2 cups blackberries; 2 to 4 tablespoons sugar (depending on sweetness of fruit); Grated zest and 1 tablespoon juice from 1 lemon; 2 teaspoons cornstarch; 2 tablespoons strawberry, raspberry or blackberry jam; 1 tablespoon milk, plus more for brushing; 1 cup confectioners' sugar