Cook peas in enough water to cover until tender, about 1.5 hours. Peel bananas & lay them whole on top of the peas without mixing. Cook for 10 minutes. Add water if necessary to prevent sticking. Meanwhile, heat the oil & brown the onions. With a slotted spoon, remove the bananas & peas & add to the onions. Sprinkle in the salt & cook over medium heat, stirring gently but constantly, until the oil has been abosrbed. Serve hot.