Take the mangoes out of the can and drain well, then puree. The juice is not needed. Mix the mango puree with yoghurt and sweeten as needed.
Whip the cream with the vanilla sugar and the cream stiffener until stiff and fold into the mango yoghurt. Carefully stir in about two thirds of the blueberries as well.
Layer alternating cream and shortbread in a flat, small baking dish. The last layer consists of the cream. Now put the rest of the blueberries on top as a decoration.