Stir together the coffee and rum and soak biscuits in the mixture. Divide between 8 individual stem glass dishes.
Layer the sliced bananas into the glasses.
Heat milk in a pan. Blend cornflour, sugar, 2 tablespoons of the milk and egg yolks together. Pour hot milk into custard mixture and return custard into the pan. Bring to the boil and thicken. Leave to cool.
Divide the custard between the glass dishes. Place in the refrigerator to chill.
To make the chocolate shapes, melt the chocolate in a bowl. Draw the shapes on a greaseproof paper. Pipe the melted chocolate on the shapes on the paper. Leave to set and peel off the paper.
Whip the double cream until stiff. Cover the top with whipped piped double cream. Sprinkle with toasted almonds. Decorate with chocolate shapes.