Make a syrup with the sugar, water and lemon salt. When it comes to the boil, reduce the heat and 2 minutes later add the cherries.
Bring back to the boil, remove from the heat and leave to stand for 30 minutes to allow the fruit to absorb the sugar. Then return to the heat and boil for 25-30 minutes or longer, carefully watching the consistency. Test for setting and remove any scum fro