Preheat the oven to 180°C/gas mark 4. Spread the panettone slices with mincemeat and cut each in half so you have 8 half-moon shapes. In a bowl, whisk together the cream, milk, caster sugar and eggs to make the custard.
Arrange the panettone slices in a 1-litre ovenproof dish and pour over the custard. Press down the panettone slices so they're covered by the custard. Sprinkle with the demerara sugar and scatter with the chopped cherries. Bake for 35-40 minutes or until the custard has set and the top is golden.