Pit the cherries. Crush the stones with a hammer and add to a large, clean preserving jar. Add the cherries and sugar and top up with brandy. Seal the jar and store in a cool dark place for around 8 weeks.
Pass the mixture through e. g. a coffee filter and transfer to small bottles. Leave to mature for around 4 months.
If desired, decorate with fresh cherries and give as a gift.