Let the blueberries thaw. Squeeze a small or half a large lemon. Bring the blueberries to the boil with the water, sugar, durum wheat semolina and lemon juice and simmer for about 5 minutes at a medium temperature. Then let the mixture cool down.
When the mixture has cooled down, use a hand blender to puree until frothy. Whip the cream with a packet of vanilla sugar until stiff and fold in loosely.
I think it`s nice to mix in some fresh blueberries to have a bite. A few frozen berries will also do - depending on their size, it takes about 2 hours in the refrigerator before they are edible.