Peel bananas and if large ones cut in half across.
Lay side by side in a buttered ovenproof dish so that they fit fairly closely.
Sprinkle them evenly with the lemon juice, then with coconut, then with sugar and finally with the rum.
Dot remaining butter over the surface and bake in the centre of preheated oven.
The dish is ready when the bananas are soft and the surface deep golden.
Serve with thin cream.
If you are feeling extravagant pour an extra tablespoon of rum into a warmed spoon, ignite, and serve the bananas aflame.