Method

1. For the sauce, put the chocolate in a heatproof bowl and add the butter. Place over a pan of simmering water and stir until melted. Stir in the cream.

2. For the banana puree, cook the butter in a frying pan until golden brown. Add both the sugars and cook until the mixture has turned a deep caramel, stirring constantly.

3. Add the chopped bananas and stir until well coated. Continue to cook for 2 minutes. Remove from the heat and stir in the lemon juice.

4. Transfer the mixture to a food processor and pulse until smooth. Leave to cool to room temperature.

5. To make the soufflé, preheat the oven to 190C/gas 5. Brush the inside of 6 large ramekins with softened butter and dust with sugar.

6. Whip the egg whites until stiff and gradually add the sugar. Continue to whip until the mixture is thick and glossy.

7. Fold half the meringue into the banana mixture, and carefully repeat with the remaining meringue. Fill each prepared ramekin with the soufflé mixture.

8. Bake for 12 minutes and serve straight away with a scoop of vanilla ice cream and a little chocolate sauce.