LINE bottom and sides of 2 1/2-quart glass bowl with about 40 wafers.
COMBINE sugar, cornstarch and salt in medium saucepan. Gradually stir in evaporated milk to dissolve cornstarch. Whisk in eggs. Add butter. Cook over medium heat, stirring constantly, until the mixture begins to thicken. Reduce heat to low; bring to a simmer and cook for 1 minute, stirring constantly. Remove from heat. Stir in vanilla extract. Let cool slightly.
POUR half of pudding over wafers. Top with half of bananas. Layer remaining vanilla wafers over bananas. Combine remaining pudding and bananas; spoon over wafers. Refrigerate for at least 4 hours. Top with whipped topping.
* A 12-oz. box of vanilla wafers contains about 88 wafers.