In a medium saucepan, combine 3/4 cup sugar, 1/4 cup flour, and a pinch of salt. Whisk together and gradually whisk in 2 3/4 cups of milk until no lumps remain.

Cook over medium heat, stirring frequently, for about 5–7 minutes until thickened and bubbly. Reduce heat to low and cook for an additional 2 minutes.

In a separate bowl, whisk 3 large eggs until smooth. Slowly pour a cup of hot pudding into the eggs, stirring constantly to temper. Pour egg mixture back into saucepan.

Return to low heat, cooking for another 2 minutes until gently boiling. Stir in 1 tablespoon of vanilla extract, then let cool for about 15 minutes.

In an ungreased 8-inch square dish, layer 25 vanilla wafers, half the sliced bananas, and half the cooled pudding. Spread evenly.

Repeat layering with another layer of wafers, remaining bananas, and rest of the pudding. Cover with plastic wrap to minimize skin formation.

Refrigerate for at least 4 hours or preferably overnight to allow flavors to meld.

Before serving, crush remaining wafers and sprinkle over the top for crunch. Serve cold.