Preheat oven to 225C / 425F / gas mark 7.

Place sugar and water in a pan and bring to a boil. DO NOT STIR. Split the vanilla pod length ways with a sharp knife and gentle scrape out the seeds. Add the vanilla seeds and about 1 tsp crushed chilli (exact amount will depend on the heat strength of your chilli and your own preference) to the syrup and simmer the mixture for 10-12 mins. At this point you can strain the syrup to remove the chilli if required.

Slice the pineapple in half lengthways and place cutside down in a baking dish. Pour over the syrup and place in the center of the oven. Bake for about 45 mins, basting regularly. Serve in slices.