A friend planning a Jamaican dinner party was looking for plantains in Hong Kong. She eventually found them at a high- end supermarket, but I've seen them in the Southeast Asian shops along Spring Garden Lane, in Wan Chai, because they're used in Philippine cuisine. Plantains are also eaten in Latin America, Africa, the Caribbean and India.
Plantains belong to the same plant family as bananas but they tend to be much heavier and thicker. Plantains are eaten as a vegetable (when they're green, hard and starchy) or as a fruit, when the skin has turned yellow (the flesh is firm and mildly sweet) or, eventually, black (softer and sweeter). Unlike bananas, plantains are not eaten raw.
The skin of the plantain is a lot thicker and tougher than that of the banana. Plantains can be ripened by putting them in a paper bag and leaving them at room temperature.
I first ate plantains at a Cuban restaurant in San Francisco, in the United States: the green plantain was peeled and the flesh cut into thin slices, which were then dipped in a light batter and pan-fried in oil before being served as a starchy accompaniment to garlicky roast pork.
At another restaurant, ripe, black-skinned plantains were cooked in a similar manner but, after being fried, they were sprinkled lightly with sugar then served with coconut ice cream. I've also eaten green plantain mash (flavoured with butter and spices) and black plantain pudding (sweetened with cane sugar and mixed with coconut milk and eggs).