In a medium bowl, combine pudding mix and milk and stir until mix is dissolved. Refrigerate 15 minutes, until partially set.

Stir condensed milk into pudding mixture until smooth. Fold in sour cream and whipped topping. Fold in bananas.

Make a single layer of vanilla wafers in the bottom of a 9x13-inch dish. Spread pudding evenly over wafers. Crush remaining wafers and sprinkle on top. Refrigerate until serving.