This satisfies the cravings for a chicken curry, and it can also be stretched with rice or noodles for those who want the full experience. I find low- or reduced-fat coconut milk is preferable to the full-fat version in a soup since it strikes a note of luxury without being overly rich. — Anne Bell, Low Carb Revolution : Comfort Eating for Good Health.
Preheat the oven to 350 degrees F.
Heat a large cast-iron casserole over medium heat, season the chicken pieces with salt, and brown on either side, then remove them to a bowl. You should be able to do this in a single batch. Add the shallots and cook in the rendered fat for a minute or so, stirring frequently, until softened and lightly colored, then add the garlic and chiles and continue to cook briefly until fragrant. Stir in the curry powder and cook for a moment longer. Stir in 2½ cups water, season with salt, then return the chicken to the pan, bring to a boil, cover, and cook in the oven for 1½ hours, stirring in the leeks halfway through.
Remove the chicken pieces and shred the flesh using a knife and fork, discarding the skin and bones. Stir the meat back into the soup base, then add the coconut milk and a little salt and gently reheat, without allowing the soup to boil. Stir in the lime juice and cilantro and serve in warm bowls sprinkled with cilantro.