In a medium saucepan over medium heat, whisk together ¾ cup sugar, ⅓ cup flour, and a pinch of salt. Gradually pour in 4 cups of milk, whisking continuously to prevent lumps. Keep stirring for about 10 minutes until the mixture thickens and begins to bubble gently, signaling it’s ready for the next step.

In a separate bowl, whisk together 3 large eggs until smooth. Slowly ladle about 1 cup of the hot pudding mixture into the eggs, stirring constantly to temper them. This step is crucial to avoid scrambling the eggs. Once combined, return the tempered egg mixture to the saucepan and mix well.

Reduce the heat to low and cook the pudding for another 2 minutes, stirring gently until it thickens further and bubbles softly. You’ll know it's done when it coats the back of a spoon. Remove from heat and stir in 1 teaspoon of pure vanilla extract for that signature flavor.

Allow the pudding to cool for about 15 minutes, stirring occasionally. This cooling phase is important as it helps prevent the vanilla wafers from getting too soggy when layered.

In an 8-inch square dish, start by placing half of the vanilla wafers at the bottom. Next, layer half of the sliced bananas evenly over the wafers. Pour half of the warm vanilla pudding over the layers, spreading it gently to cover all the bananas and wafers completely.

Repeat the layering process by adding the remaining sliced bananas on top of the pudding. Then, pour the rest of the pudding over this banana layer, ensuring it is evenly distributed.

Cover the dish tightly with plastic wrap and refrigerate for at least 4 hours, although overnight is best for flavor development and texture.

Just before serving, crush the remaining vanilla wafers and sprinkle them generously over the top of the pudding for added texture and crunch.