For the cherry-coconut jam, rinse the cherries with cold water, remove the stems and pit (best done with a cherry corer).
Grate ½ tsp lemon zest, squeeze out the juice. Place the cherries in a saucepan with 5 tablespoons water, lemon juice and zest, and the preserving sugar. Bring to a boil and simmer for 5 minutes until bubbling. Only mix in the coconut flakes towards the end.
Make the jelly test. To do this, drip some of the jam onto a cold plate. If it sets, the jam is ready. If not, let the mixture cook a little longer.
Pour the cherry-coconut jam into prepared twist-off glasses. Drizzle a little alcohol over the top, light and seal immediately. Place with the lid down on a tea towel and let cool.