Add the milk, heavy cream, egg yolks, sugar, and cornstarch to a large saucepan set over medium-high heat. 

Cook, whisking constantly until the mixture thickens enough to coat the back of a spoon, about 5-7 minutes. 

Stir in the vanilla extract and cover the pudding with plastic wrap.

Transfer it to the fridge until chilled, about 1 hour. 

Place a heatproof bowl over a pot of simmering water. 

Place the egg whites and granulated sugar in the bowl and whisk constantly until all of the sugar has dissolved, about 2 minutes.

Transfer the mixture to the bowl of a hand or stand mixer fitted with the whisk attachment and mix on high speed until stiff peaks form, about 8 minutes.

Add the vanilla extract and mix just until combined.

Set aside until ready to use. 

Cover the bottom of your serving dish with Nilla Wafers. You can either do one big serving dish or individual cups.  

Cover with a layer of pudding followed by a layer of sliced bananas. Repeat until all components are completely used, making sure the last layer is pudding. 

Spread or pipe the meringue evenly over the custard layer.

Toast the top of the meringue with a kitchen torch until golden brown, about 10 seconds. 

Serve immediately or store the pudding in the fridge until ready to enjoy, up to 4 hours in advance.