Add 1 sliced banana, ½ Cup of crushed vanilla wafers and the pudding mix to a medium mixing bowl.
Pour the 2 cups of milk into the mixing bowl and mix well with a whisk. Cover and place in the refrigerator while you prepare the rest.
In a small bowl melt the butter and add the granulated sugar and 1 teaspoon of vanilla, stir to mix well.
Brush this butter over both sides of a tortilla. Stand up in the crease of the back of a muffin tin (not a cupcake tin - muffin tins are bigger). You should be able to bake 2 at a time like this.
Place the muffin tin (with the tortillas) into the oven and bake for about 10 minutes. Watch closely - the edges should turn a golden brown when they're ready.
Remove from the oven and sprinkle a little more sugar over while they're still hot.
Repeat with the remaining taco shells until they have all baked and cooled.
Add the cream, vanilla and powdered sugar to a separate bowl and beat until stiff peaks form.
Place the baked tacos into a dish, all standing upright. Fill to ⅔ full with the refrigerated banana pudding.
Slice the remaining sliced bananas and arrange on top along with a little more crushed vanilla wafers.
Top with the whipped cream and sprinkle with crushed vanilla wafers.
Notes
Making the vanilla taco shells will not work with a regular cupcake pan as it will be too small - if you don't have a muffin tin you could lay them down flat on a baking sheet and place something on the inside of a folded tortilla that is oven proof. A small ramekin maybe.
Using instant pudding mix does make an easy banana pudding. If you prefer to make your own pudding.
You could use mini vanilla wafers if you prefer.
When mixing the banana pudding you could use a stand mixer with the paddle attachment, if you have one. It'll help mix it nicely. It's not totally necessary though.
You could make the tortillas yourself too, if you're feeling up to it. It will add more time to the preparation time though. Search for a dessert tortilla recipe - add a cup of batter to a pan and allow tortillas to cook for a minute or two. You'll probably need all purpose flour, an egg mixture and some sugar.
I've heard of people using those little snack pack puddings to make this. I guess it could work if you don't mind that pudding.
Make your banana pudding mobile. Take an individual packet of vanilla wafers and spoon your banana pudding mix into it, with some cream and a disposable spoon. Now you have walking tacos.