Chocolate Shortcakes With Sour Cherry Topping

For cherry topping: In small saucepan combine all topping ingredients and cook over medium-high heat, until cherries start to release their juice and the liquid thickens and becomes syrupy, 6-7 minutes; cool and refrigerate until needed (you can make this up to 1 day ahead).
For shortcake biscuits: Preheat oven to 350F and set rack in middle of oven; combine all dry ingredients in a large bowl until blended; rub butter into flour mixture with your fingertips until mixture resembles coarse meal; in a small bowl, whisk egg yolks with buttermilk to blend; add to flour mixture and stir just until evenly moistened; turn dough out onto a floured board and, with lightly floured hands, knead just until it comes together (if the dough is very sticky, sprinkle on some additional all purpose flour); pat out to about 1 1/4 inches thick and cut into rounds with a 3 inch cutter; gather dough scraps and pat out again to make remaining shortcake biscuits; set 2 inches apart on a large baking sheet; bake biscuits for approximately 25 minutes, or until golden-brown, and transfer to a rack to cool completely.
For whipped cream: Beat cream, sugar and vanilla until soft peaks form.
To assemble: Slice shortcake biscuits in half and set bottoms of biscuits on 6 dessert plates; dollop generously with whipped cream and distribute cherry topping evenly over the cream; place biscuit tops over cherries at a slight angle and sprinkle tops lightly with confectioners' sugar.