01 -
In a medium saucepan, combine sugar, cornflour, and salt, whisking thoroughly. Separately, whisk milk, cream, and egg yolks in a bowl until smooth. Gradually pour this mixture into the saucepan, whisking as you go to keep it lump-free. Cook over medium heat, stirring the whole time, until the mixture thickens (10–15 minutes). Once thickened, remove the pan from heat, strain the pudding through a sieve to remove any bits, and stir in the vanilla and butter. Place plastic wrap directly on the surface, then refrigerate to cool completely.
02 -
Beat cold heavy cream, powdered sugar, and vanilla on high speed using a mixer until you see stiff peaks form. Save one-half for topping later, then gently fold the other half into the chilled pudding until it's mixed evenly.
03 -
Slice the bananas thinly (about ⅛-inch thick). Use a pastry brush to coat both sides of each piece with a light layer of lemon juice so they stay fresh-looking.
04 -
Spoon a light layer of the pudding at the bottom of a 2.5-quart dish. Arrange a layer of cookies, then lay down banana slices on each cookie. Cover this with half the pudding. Repeat with more cookies, bananas, and finish with the rest of the pudding. Finally, spread the remaining whipped cream neatly on top.
05 -
Put the dessert in the fridge, covered, for a minimum of 4 hours or even better, overnight for up to 24 hours. When ready to serve, crush a few cookies for garnish and sprinkle chocolate shavings if you'd like.