Preheat oven to 500 degrees. Thaw fish if still frozen under cold running water. Crush plantain chips in a blender or food processor until fine. Melt butter in a medium size bowl. Dip one side of each haddock fillet in the melted butter and then in the crushed plantain chips. Place on a lightly greased rimmed baking sheet in a single layer. Bake for about 13 minutes or until fish easily flakes with a fork.