For the peach cognac jam, wash the jars and lids, boil and disinfect with a little brandy. Wash the peaches, cut the fruit into halves. Peel off the skin and remove the seeds.
Cut the flesh into small pieces or puree with a blender. Sprinkle with lemon juice. Mix the jelling sugar with the peach mixture and let it infuse for about 4-5 hours.
Then boil the mixture for 4-5 minutes. Skim peach cognac jam if necessary. Stir in vanilla and cognac.
Pour the peach-cognac jam into the prepared jars as hot as possible and seal immediately.