Preheat the oven to 175 C. Spread the coconut shavings over a baking plate and bake in the oven. Be careful as it takes only a few minutes and browns real easily, so stay close to the oven and check regularly until golden and brown.
Put the milk together with the roasted coconut into a small saucepan and bring to the boil. Turn of the heat and leave to stand for about 30 minutes.
Mix the sugar, the coconut milk and the double cream in a bowl. You can sieve out the coconut or leave it in, as I did. If you want to take it out, make sure you squeeze all milk from the coconut.
Add the booze and the zest to the mix, Stir well and put in the fridge to bring down to very cool before adding into your ice cream maker.