In a large pan, heat up the oil and fry the onions until translucent, then add the garlic and fry for a minute before adding the chillies.
Cook for 3 minutes more, then add the cubed meat and brown all sides. Once the meat is browned, add the tomato paste, raisins, curry powder and all the spices.
Stir and cook for a minute, then add the coconut milk and bring it to a boil.
Immediately reduce to a simmer and add the plantains.
Cover and simmer gently for 30 minutes (checking occasionally that it doesn't become too dry, add a little water if neccesary).
Serve immediately with rice.