This recipe is a variation on tabouli - it substitutes the cracked wheat with green shredded plantain.
Peel and cut plantain into three inch pieces, and boil to cook until it gets soft and changes color, for 20 or 25 minutes. Drain and let cool just enough until you can handle it without burning, and shred coarsely (shredded plantain will faintly resemble macaroni).
While plantain cools, mix the lemon juice with the onion and leave for 10 minutes (this will cook the onion so it loses some of its metallic bite). Then add olive oil and salt and pepper to taste. When throughly cooled, mix with herbs and serve chilled.
* Variation: you can subtitute the spearmint leaves with some fresh coriander leaves.