Finely mince one of the pieces of ginger and slice the other into fine matchsticks. Set aside.
Heat the oil in a large pan over a medium heat. Add the onions, garlic and minced ginger and fry, stirring continuously, for 8 minutes, until golden brown.
Add the chicken to the pan and stir to combine with the onions, then add the garam masala, ground coriander, ground turmeric and chilli powder. Cook, stirring occasionally, for 5 minutes, to seal the chicken and coat it in the spices.
Add the creamed coconut, coconut milk, ginger matchsticks, sliced chillies, salt, sugar, pineapple and cashews to the pan and stir to combine, adding a little of the juice from the canned pineapple if the mixture is too dry.
Leave to cook, stirring occasionally, for 5–10 minutes, until the chicken is cooked through. Scatter with chopped coriander/cilantro and sliced red chilli, then serve hot with rice or wraps alongside.