The selected berries (all unripe must be removed), rock sugar, vanilla sugar and red wine (it does not have to be the most expensive) in a sufficiently large saucepan and then simmer for an hour and stir more often (tends to boil over).
Allow the approach to cool properly and then strain through a cloth and squeeze out vigorously.
Then add the grain, stir well and fill into bottles.
After at least 2 weeks, it is ready to be enjoyed.