For the hazelnut liqueur, finely chop hazelnut kernels and pour into a large glass. Pour the spirit of wine over them and close the jar tightly.
For 4 weeks, if possible, place in the sun and shake well once a day. After 4 weeks, pour the mixture through a sieve, add cinnamon, clove powder and orange peel and leave it well closed for another week.
Boil sugar with water, then let cool. Add the sugar solution to the nut-spice mixture and stir well. Pour the finished liqueur through a filter into clean bottles.