Separate the egg yolks from the egg whites and put them into separate bowls. You will use the egg yolks in the pudding and the egg whites in the meringue. Keep them at room temp.
Measure out all of your ingredients for the pudding.
Mix ¼ cup of the whole milk with the cornstarch to make a cornstarch slurry. Set aside.
Homemade Vanilla Custard/Pudding
Add the remaining milk to the inner pot of the Ninja Foodi or Instant Pot or to a pot on the stove. Add in the sugar and salt. Stir to combine and heat over high to medium high heat until the milk begins to steam. You do not want to boil the milk. Stir occasionally to prevent scorching.
While the milk is heating, lightly beat the egg yolks and make sure the bowl is big enough to whisk in ¼ cup of the hot milk.
Once the milk is steaming, reduce the heat to low-medium to prevent scorching. Remove ¼ of the hot milk mixture and slowly stream it into the egg yolks while whisking constantly. This will temper the egg yolks which helps to prevent them from cooking when they are added to the hot milk.
Slowly stream in the tempered egg yolks into the hot milk, whisking the milk the entire time. Whisking is better than stirring because it brings more air into the milk and cools it down so the eggs don't cook. Once all of the egg yolks are incorporated, add in the cornstarch slurry. You may want to stir the slurry to make sure it didn't settle while sitting.
Continue whisking constantly until the pudding starts to thicken. The cornstarch needs heat to activate, but you don't want the pudding to be too hot or it will burn. Adjust your heat accordingly. As soon as the pudding starts to thicken, turn the heat off and continue to whisk while it thickens up more.
Remove from the heat and whisk in the vanilla extract. Transfer to a glass bowl and cover with cling wrap. Make sure to have the cling wrap touching the top of the custard so it doesn't form a skin. Refrigerate for about 2 hours.
Place the heavy whipping cream into a bowl of a stand mixer or a glass/metal bowl if using a hand mixer. Begin whisking on medium speed until the cream starts to thicken and then whisk on high speed until you see peaks forming in the cream.
When the custard has cooled, fold in the whipped cream. Remove the cling wrap, and stir the pudding. If you see steam, it is not cool enough and should be returned the to fridge. Add about 1 cup of the heavy cream on top of the custard and gently fold the cream into the custard until you barely see any white from the whipped cream. Repeat until all of the whipped cream is used.
Cover and refrigerate if you aren't using right away.
Meringue Topping
Make sure your mixing bowl is clean and dry. Any traces of fat will prevent the egg whites from whipping up.
Add the egg whites to the bowl of a stand mixer or a medium bowl if using a hand mixer. Whisk on high speed until they start to thicken. Add in ½ Tablespoon of sugar at a time and whisk on high until incorporated. Repeat for the remaining 1½ Tablespoons.
The meringue is done when soft peaks form. Some people like to see stiff peaks, but I found it is very easy to over whip the egg whites and that makes it harder to spread on the top of the pudding without deflating the meringue.
Assembling the Banana Pudding
Preheat the oven on 375°F/190°C
While it doesn't really matter if you use a casserole dish or a bowl for your banana pudding, you will want something that is around an 8"x8" with at least a 3" depth. Anything larger and you will need to increase the ingredients. For a 9x13 pan, double all of the ingredients.
Place a layer of cookies on the bottom of your pan. Add banana slices that are about ½" thick. Cover with half of the pudding mixture and spread it out so it covers all of the bananas. Repeat with a second layer of cookies, banana slices, and the remaining pudding.
Top with a layer of cookies and then gently spread the meringue over the top. Use the back of a spoon to make the peaks in the meringue.
Place the dish in the oven so that it is near the top, but the meringue is not too close to the heating element. Bake for 7-10 minutes or until the peaks turn golden brown.
Remove from the oven and chill for at least 4 hours, but overnight is even better!
Decorate with more cookies on top just before serving. Serve & Enjoy!