For the apricot-nectarine jam, cut apricots and nectarines into small pieces and mix with the preserving sugar, leave to marinate for a few hours.
Mix the fruit mixture with the citric acid, bring to the boil and boil for 5 minutes until bubbling. Pour the apricot-nectarine jam into sterile screw-top jars and seal immediately.
Preparation Tip:
Refine the apricot-nectarine jam with a little vanilla.