In a medium saucepan over medium heat, combine 3 cups of half and half, the seeds and pod from 1 vanilla bean, and ⅛ teaspoon of nutmeg. Bring to a simmer.

Whisk together ¾ cup of granulated sugar, ¼ cup of cornstarch, ¼ teaspoon of salt, and 5 large egg yolks until pale and fluffy.

Gradually pour the simmering half and half into the egg mixture while continuously whisking.

Return the mixture to the saucepan and cook over medium heat, stirring constantly until thickened.

Remove from heat and stir in 1 tablespoon of butter until melted, then transfer to a heatproof bowl.

Cover with plastic wrap directly on the pudding's surface and chill for at least 2 hours.

Layer 30 vanilla wafer cookies in an 8x8 inch dish, followed by half of the pudding, sliced bananas, and another layer of cookies.

Spread the remaining pudding over the top layer evenly and return to the refrigerator for another 2 hours.

Whip 1 cup of heavy cream with 2 tablespoons of granulated sugar and ½ teaspoon of vanilla extract until stiff peaks form.

Spread whipped cream over the top layer and garnish with banana slices and crushed vanilla wafers before serving.