In a saucepan, combine mango cubes, brown sugar, cornstarch, cardamom & lemon juice. Heat for a few minutes just to thicken slightly; remove from heat & cool. Roll out pastry & cut 8 -6″ circles. Lay pastry circles on parchment lined baking sheet & divide filling between them. Try to keep the filling piled in the center , away from the outer edges. Use a fork to press the pastry layers together around the outside forming a seal. With a sharp knife cut 3 vents in each hand pie.