Place the apricots into a stainless steel heavy bottomed pan along with the sugar and the stones.
Cut the vanilla pod into small pieces and scatter over the sugar.
Squeeze in the lemon juice and add a splash of water.
Cover the pan with a lid and leave overnight for the flavours to infuse.
Bring the mixture to a gentle simmer and stir until the sugar is completely dissolved.
Bring it to a rapid boil and let it go for a good ten minutes or until the jam goes from frothy to clear to setting point. Test for setting point by dropping a teaspoonful onto a cold plate. If the jam wrinkles when it's pushed, it's ready.
Remove the stones with a spoon and ladle the hot jam into two sterilised jars. Cover, seal and label.
Notes
Keep a plate in the freezer so it's nice and cold when you test the jam.Please note: calories and other nutritional information are per serving. They're approximate and will depend on exact ingredients used.