Put all the paste ingredients into a food processor or blender and whiz to a thick paste, pushing the mixture down from time to time with a spatula.
Transfer to a glass bowl, cover tightly (otherwise it will taint everything in the fridge) and refrigerate. You can make this up in advance and freeze it if you prefer.
Mist the pan with low-calorie cooking spray. When hot and sizzling, add the chicken and let it colour on all sides.
Remove the cooked chicken chunks from the pan. Place your paste in the pan and fry it off for a minute.
Pour in the coconut drink and the rest of the curry ingredients, except the chicken. Stir, bring to the boil, then turn the heat down and simmer for 10 minutes (stirring from time to time).
Return the chicken to the pan and simmer for 5-6 minutes, or until the chicken is cooked through.
Thicken if you don't like it too runny, and serve.
Place 200ml (¾ cup) of the sauce into a jug and whisk in the Xanthan gum a ¼ of a tsp at a time. You will need to whisk well and keep whisking!
Return the thickened sauce to the pan and stir well - it will thicken the curry!