Off-heat, whisk in butter until melted and thoroughly combined. Then whisk in the vanilla paste. If you sense any lumps, strain the pudding through a fine-mesh sieve set over a heatproof medium bowl. Immediately place plastic wrap or buttered parchment paper directly on the surface of the cream to prevent a skin from forming. Transfer bowl to prepared ice bath to chill for 30 minutes, then refrigerate until cold, about 2 hours.
When you are ready to make the pudding mixture, pull the pudding from the fridge to loosen up. Use a whisk to completely loosen it, removing as many lumps as possible, so that it will easily blend into the whipped cream (next step)
If using one trifle bowl, I would use all five medium bananas. For the smaller glasses, you will definitely need less.
Take three or so of the cookies and grind down to coarse crumbs. You can use a mortar and pestle, food grinder, or just place in a freezer bag and run a rolling pin over it till cookies are crushed. Set aside.
Lay out one layer of the cookies you are using. Lay banana slices over the cookies. Keep cutting up bananas as needed. Don't be stingy. Save enough cookies for garnish on top, about five or so for the large bowl, and one per glass if using individual jars.
Lay out the final cookies on top of the pudding and sprinkle with the coarse cookie crumbs.
You can also garnish with some banana slices that you have gently brushed with a small amount of fresh lemon juice. This will help them from browning if the pudding will be sitting out for a while.
I say this feeds six, but it can feed up to eight, especially if served from the trifle bowl, or if the glass jars you are using are on the smaller side.
If your jars have lids, spoon the pudding up to the top and cover with lids to store in the fridge till ready to serve. They will need a good four hours for the pudding and cookies to meld.
Once you remove the lids you can finish garnishing and then serve.
The vanilla pudding itself is a wonderful dessert that you can serve with fresh fruit, or spooned on the side of a slice of pound cake.