Wash cherries, remove stalks. Stone the fruit. Mash half of the cherries with a fork. Halve the remaining cherries.
Mix everything with jam sugar, add kirsch and let it stand covered for about 2 hours. Bring to the boil while stirring and continue to boil for about 4 minutes until sparkling. Skim off foam if necessary. Pour hot jam into prepared, sterilized jars and close tightly immediately
2 hours waiting time