Wash and pick over the black eyed peas, then place in a pot, cover with plenty of water and boil for 2 minutes.
Remove from the heat and set aside for around 90 minutes to soak, then return to the heat (use the same water), bring it to a boil, reduce to a simmer and cook covered for about 2
Add the onions, tomato and chillies to the beans and cook uncovered for around 15 minutes. Now add the tomato purée, oil and the prawns.
Cover and simmer for 10 minutes (do not stir).
Remove the cover and continue cooking for 5 minutes more or until the mixture is quite dry (we prefered to keep it more soup like, personal taste).
Sprinkle the plantains with sea salt, then deep fry in oil until golden brown. Drain on kitchen towels. Serve the Black-Eyed Pea stew with the fried plantains.