Tip the buttery crumbs into the middle of your deep tart tin. Press the mixture firmly into the base and up the sides using your fingers. Place the tin into your fridge for 30 minutes until it feels cold and firm.

Melt the rest of your butter in a medium non-stick saucepan over low heat. Stir in the dark brown sugar with your wooden spoon until it dissolves fully. Ensure no oil floats to the top of your smooth brown mixture.

Pour the thick condensed milk into the sweet pan and bring it to a simmer. Stir the liquid constantly for three minutes until it turns a deep caramel color. Pour this hot toffee over your chilled biscuit base and smooth the top.

Put the pie back into the fridge to cool for at least one hour. Lightly whip your double cream in a large bowl until it forms soft peaks. Slice four of your bananas diagonally into clean pieces on a chopping board.

Scatter half of the fruit slices over your cold, firm toffee layer. Fold the rest of those sliced bananas gently into your bowl of whipped cream. Spoon the creamy mixture over the pie and spread it out evenly.

Slice your last banana and place the pieces into a small clean bowl. Pour your fresh lemon juice over the fruit and toss the pieces gently. Decorate the top of your pie with these wet slices.

Grate your dark chocolate over the fluffy cream using a fine hand grater. Take the pie out of the tin carefully and place it on a plate. Cut the dessert into thin slices and serve it to your guests.