For 10 shortbreads sugar, icing sugar, salt and soft butter in flakes in a bowl.
sel and stir with the whisk of the mixer until creamy. Add flour and knead with your hands to a smooth dough. Wrap in cling film and chill for about 30 minutes.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Line a baking tray with baking paper. Roll out the dough on a floured work surface to a thickness of approx. 8 mm. Cut out approx. 10 circles (approx. 6 cm Ø), kneading the dough again and rolling out and cutting out again.
Put dough circles on the baking tray and bake in a hot oven for about 20 minutes until the cookies are lightly browned. Take them out and let them cool down.
If you don't have the time to bake, you can also buy good quality shortbread, for example from Walkers.
Sort and wash the blackberries. Bring to the boil in a saucepan with 2 tablespoons of sugar and 6 tablespoons of water. Cover and simmer for about 2 minutes. Stir starch with 1 tbsp. water until smooth. Stir into the blackberries and simmer for about 1 minute.
Remove from the heat, crush blackberries slightly if necessary. Leave to cool down.
Coarsely crumble 4 shortbreads and divide into six large glasses (approx. 250 ml each). Add 1 tbsp. blackberries to each.
For the cream, pour the sour cream, cream and 2 tablespoons of sugar into a tall mixing bowl and whisk until stiff. Loosely fold the blackberry sauce into the sour cream, except for 3 tbsp.
Spread the sour blackberry cream into the glasses, add the remaining blackberries.