In northern Peru they make a dish called "majau" that's a great substitute for rice. Boil the green plaintains, skin and all, for about 20 minutes or until softened. Cool and peel the plantains. Using a masher or fork, mash them. You'll need to heat some olive oil in a skillet and sautee the mashed plantains until they're golden brown and crunchy. Serve alongside beans or any other meal you'd eat with rice. If you don't like the idea of sauteeing, you could instead form the mashed plantain into balls. Drop the balls into hot chicken broth and cook them for several minutes for a delicious chicken soup with Carribean flare. I hope that helps!