To make the toffee, place the unopened tin of condensed milk in a pan of water and boil for 3 hours, topping up with boiling water as necessary. Leave the tin to cool, and the toffee is ready!
While the tin is boiling, roll out the pastry and use to line the flan tin or rings. Line the pastry with greaseproof paper, fill with baking beans and
To make the crumble, rub the flour and butter together until the mix is like fine crumbs, then add the sugar. Chop the bananas and spoon into the flan cases. Top with the toffee from the tin and sprinkle with the crumble.