Step 1: Prepare the Bananas

1. Slice the Bananas: Peel and slice the bananas into 1/4-inch thick rounds.
2. Toss with Lemon Juice: Place the banana slices in a bowl and toss them gently with lemon juice. The acid in the lemon juice will help prevent browning. Set aside.

Step 2: Make the Pudding

1. Heat the Milk: In a medium saucepan, heat the milk over medium heat until it’s warm but not boiling.
2. Mix Dry Ingredients: In a separate bowl, whisk together the sugar, cornstarch, and salt.
3. Combine with Egg Yolks: Add the egg yolks to the dry ingredients and whisk until smooth.
4. Temper the Eggs: Slowly pour the warm milk into the egg mixture, whisking constantly to prevent curdling.
5. Cook the Pudding: Return the mixture to the saucepan and cook over medium heat, stirring constantly, until the pudding thickens and coats the back of a spoon, about 5-7 minutes.
6. Add Butter and Vanilla: Remove the saucepan from the heat and stir in the butter and vanilla extract until fully incorporated.

Step 3: Assemble the Pudding

1. Layer the Wafers and Bananas: In a large serving dish or individual bowls, layer vanilla wafers and banana slices.
2. Add the Pudding: Pour the warm pudding over the layers, ensuring the bananas and wafers are fully covered.
3. Repeat Layers: Add another layer of wafers and bananas, followed by the remaining pudding.

Step 4: Make the Whipped Cream Topping

1. Whip the Cream: In a large bowl, beat the heavy cream, powdered sugar, and vanilla extract until stiff peaks form.
2. Top the Pudding: Spread the whipped cream evenly over the pudding.

Step 5: Chill and Serve

1. Refrigerate: Cover the pudding with plastic wrap and refrigerate for at least 4 hours, or overnight, to allow the flavors to meld and the wafers to soften.
2. Serve: Garnish with additional banana slices or crushed vanilla wafers before serving.