In a small pot, heat milk on medium-low (if using vanilla bean, slice it open and scrape seeds into pot, and toss the bean in too).  Stir occasionally, and heat until milk becomes frothy (without boiling). Should take about 5-10 minutes, but a bit longer if using 1% or 2% milk.

In a metal bowl, whisk the egg yolks with the sugar.  Then add in the flour and salt, and whisk together.

Add a quarter of the heated milk into the bowl, while constantly whisking (to prevent the eggs from cooking).  Then repeat with another quarter of the milk.  Finally, pour everything in the bowl back into the pot, while continuing to whisk.

Return the pot to the stove and turn fire on low.  Whisk constantly to prevent the mixture from cooking on the bottom of the pot.

Without allowing it to boil, heat until the mixture thickens into a creamy pudding (the pudding will thicken even more once it cools).  Should take around 10 minutes.  Turn heat off and let sit for 5 minutes, stirring frequently to cool the pudding.

Whisk in the vanilla extract (or vanilla paste) and lemon juice. Let sit for another 5 minutes.

Cover with plastic wrap, pressing the plastic down on the pudding to prevent a skin from forming. Chill in refrigerator for a few hours (if not serving that day, transfer to airtight container, and store up to three days)

Once chilled and ready to serve, stir the pudding until creamy, and add in banana slices (and rum, if using).  Take out the chilled cream and whip it up until thickened (recipe and tips for sugar-free whipped cream).

If you want to make a rum whipped cream, add in a tablespoon of rum and a couple teaspoons of sugar to the cream once it begins to thicken.

Add pudding into glasses and top with whipped cream.  Garnish with thin slices of orange peel.  Add whole wafer or crush waffle cones