In another bowl, combine the sugar and cornstarch. Add the blackberries and mix gently until the sugar is moistened. Divide the blackberry mixture evenly among the circles of dough, placing it in the centre. Fold the edges of the dough toward the centre, over the filling but not completely covering the blackberries, forming pleats as you go. Transfer to the baking sheet. Brush the dough with the egg wash and sprinkle with sugar.
RICARDO Rolling Pin
Every good cook should have this rolling pin in their kitchen. It is worthy of professional pastry chefs. This rolling pin is non-stick and solid, and hard wood handles provide stability and comfort.