Wash, peel and halve the pears and remove the core. Boil 1/4 litre of water, wine, 2 tablespoons of sugar and the juice of 1/2 lemon. Steam pear halves in it at low heat for 12-15 minutes.
Remove (use liquid for other purposes) and let it cool down. Stir mascarpone, remaining sugar and remaining lemon juice until smooth. Sort the blackberries, wash them and, except for a few berries for garnishing, puree them with a chopping stick.
Then pass through a sieve and season to taste with vanilla sugar. Cut 4 pear halves into slices. Fill the other halves with mascarpone cream. Arrange the pears on a plate and pour the blackberry sauce over them.
Garnish with mint and remaining blackberries. Serve sprinkled with icing sugar.