Banane Jaune avec Sauce Blanche

• 5 large green plantains, or 6 fairly small green bananas
• 1½ oz. unsalted butter

Peel the plantains or bananas by cutting through the skin lengthwise with a sharp knife in 3 places, then peeling off the skin. Cut the plantains in half cross-wise. The bananas should be left whole. Put into a saucepan with salted water to cover and cook until tender, about 30 minutes for the plantains, 15 minutes for bananas.

Heat the butter in a small saucepan and stir in the flour.