20 minutes + 1 hour to cool
2 x 400 ml/14 oz cans sweetened condensed milk 6 tbsp butter, melted 150 g/5!4 oz digestive biscuits, crushed into crumbs 50 g/1 oz almonds, toasted and ground 50 g/1 % oz hazelnuts, toasted and ground
4 ripe bananas 1 tbsp lemon juice 1 tsp vanilla essence 75 g/2 oz chocolate, grated 450 ml/16 1 oz thick double cream, whipped
Place the cans of milk in a large saucepan and cover them with water. Bring to the boil, then reduce the heat and simmer for 2 hours. Ensure the water is topped up regularly to keep the cans covered. Carefully lift out the hot cans and leave to cool.
Preheat the oven to 180°C/350°F/Gas Mark 4. Grease a 23-cm/9-inch flan tin with butter. Put the remaining butter into a bowl and add the biscuits and nuts.
Mix together well, then press the mixture evenly into the base and sides of the flan tin. Bake for 10-12 minutes, then remove from the oven and leave to cool.
Peel and slice the bananas and put them into a bowl. Sprinkle over the lemon juice and vanilla essence and mix gently. Spread the banana mixture over the biscuit crust in the tin, then open the cans of condensed milk and spoon the contents over the bananas. Sprinkle over 50 g/1 oz of the chocolate, then top with a thick layer of whipped cream. Scatter over the remaining chocolate and serve.