Into a large heat-proof bowl, add Granulated Sugar (2/3 cup), All-Purpose Flour (4 tablespoon), and Sea Salt (1/4 teaspoon). Whisk to combine.
Add Whole Milk (3 cup). Whisk to combine.
Add Vanilla Extract (1/2 tablespoon) and Vanilla Bean Paste (1/2 teaspoon). Whisk to combine.
Place bowl over a pot of boiling water to create a double boiler, ensuring that it does not touch the water. Allow mixture to heat for about 5 minutes, stirring often with a wire whisk.
Add Egg (3) yolks and mix until everything is well combined. Use a spatula to scrape down the sides of the bowl to make sure there is no pudding building up on the sides of the bowl. This will also help prevent lumps from forming. Cook for 10-15 minutes, stirring the mixture with a whisk every 2 to 3 minutes.
Spread half of the Vanilla Wafers (24 ounce) across the bottom of a large pan or casserole dish. Spread Banana (3) evenly across the top of all the vanilla wafers. Top with remaining vanilla wafers.
Once the mixture has thickened, remove from the heat and pour evenly across the top of the prepared pan of bananas and wafers. Gently fold everything together, allowing the mixture to coat everything.
Allow the mixture to cool on the counter for 15 minutes.
Cover with cling film and chill in the refrigerator for 1 1/2 to 2 hours.
Pour Heavy Cream (1/2 pint) into the bowl of a stand mixer fitted with a whip attachment.
Turn stand mixer on low and whip for 1 minute.
Add Caster Sugar (4 tablespoon) and mix on medium speed for 1 minute.
Turn the mixer up to high speed and whip for 20-30 seconds. The mixture will be pretty close to stiff peaks. Pour in the Vanilla Extract (1 teaspoon) and whip for another 5-10 seconds on high.
Allow the bowl and the whip attachment to sit in the freezer for at least 20 minutes.
Top the pudding with whipped cream. Serve and enjoy!