Preheat the oven to gas mark 5 (400F).
Lightly grease a 10in x 1.5in flan tin. Line this with the pastry thinly rolled out. Prick the base all over with a fork and bake blind until crisp. Allow to cool.
The secret of this delicious pudding lies in the condensed milk. Immerse the cans unopened in a deep pan of boiling water. Cover and boil for 5 hours making sure that the pan does not boil dry* (see CAUTION).
Remove the tin from the water and allow to cool completely before opening. Inside you will find the soft toffee filling (or use dulce de leche)
Method: Whip the cream with the instant coffee and sugar until thick and smooth. Now spread the toffee over the base of the flan. Peel and halve the bananas lengthwise and lay them on the toffee. Finally spoon or pipe on the cream and lightly sprinkle over the freshly ground coffee.
*CAUTION: It is absolutely vital to top up the pan of boiling water frequently during the cooking of the cans. 5 hours is a long time and if they are allowed to boil dry the cans will explode causing a grave risk to life, limb and kitchen ceilings. Serves 8-10.
