(So named for historical reasons which need not concern us here. Serves a smallish party, or a very greedy family.)
You will need:
around ½ a packet of digestive biscuits
[possibly butter and golden syrup]
toffee [see below]
8 to 10 bananas (overripe and/or bruised are fine)
1 pint of whipping cream
Making the toffee
The classic technique is to buy a couple of tins of condensed milk, and carry out the following surprising procedure on them.
Place the tins -- full, intact and unpierced -- in a large pan of boiling water. Boil them persistently for around four hours, topping up the water frequently. Provided you remember that last bit, the tins will not explode.
At the end of this, take the tins out and place them in cold water to cool. When you open them you will, I promise, find that the inside of them has turned into toffee of a spreadable consistency.
Alternatively, if you're no longer a cheapskate student, you can buy this stuff instead. Mmm.
Assembling the pie
Put the biscuits in a bag and smack them about with a rolling pin until they've gone all crumbly. This can be a good way of working out frustration with work, or with your love life.
Either put the biscuit crumbs neat into a greased dish, or else microwave them for a couple of minutes, stirring every 30 seconds or so, with a spoonful of syrup and a couple of knivesful of butter, to turn them into a biscuit base. Neat works fine, though.
Spread liberally with toffee. Don't forget to clean the knife afterwards. Mm.
Mash the bananas.
Yes, I said mash them. Sliced-banana banoffee is an abomination unto the Lord.
No, it's not going to end up too sweet. It's all under control, I promise.
Now spread mashed banana over the layer of toffee. God, that looks good. Yes. Yes.
Add a couple of spoonsful of instant coffee to the cream (you can use decaff if you're feeding children or unusually susceptible guests). Whip the cream until it's stiff and fluffy, like a randy bunny-rabbit.
Spread liberally over the layer of banana. Sprinkle with a spoonful of ground coffee (again, decaff if necessary). The bitterness of the coffee will offset the sweetness of the banana, bringing the sweetness of the whole within manageable levels.
Put in the refrigerator to set. Probably not for too long, though. It doesn't keep at all well, more's the pity.