In a large pot, combine the apples, pears, plums, 1/2 cup water, the honey, vanilla and cinnamon. Bring to a boil, reduce the heat, cover and cook for 30 minutes.
Remove the lid and continue cooking until the syrup is reduced and the fruit is tender, another 30 minutes.
Cool completely, cover and store in the fridge until ready to serve. Serve alone or on cake.