Heat the slow cooker. Season the chicken, then put the oil in a wide frying pan and, once hot, add the chicken. Don’t overcrowd the pan – you may want to do this in batches. Cook over a high heat until the chicken is browned, then transfer it to the slow cooker. Add the onion, garlic and ginger to the pan and cook for a few mins until softened. Add a splash of water and scrape any bits from the bottom of the pan, then tip everything into the slow cooker.
Add the remaining ingredients, except the cream and coriander, then season well and cover with a lid. Cook on low for 5-7 hrs or on high for 4-5 hrs.
Add the cream and check the seasoning, adding more vinegar, sugar or salt if needed. Cook for another 10-15 mins until hot. Ladle between bowls and garnish with the coriander. Serve with rice, naan bread and lime wedges, if you like.