Start by spraying a 9 x 13 inch baking pan with non-stick spray to prevent the treats from sticking.

In a large microwave-safe bowl, add 3 tablespoons of butter and microwave it for about 30 seconds until melted.

Add an entire bag of marshmallows to the melted butter and stir until well-coated. Microwave for another 45 seconds and stir again until smooth.

Incorporate the instant banana pudding mix into the marshmallow mixture and stir until no lumps remain.

Gradually fold in 6 cups of Rice Krispies cereal until evenly coated.

Pour the mixture into the prepared baking pan and press down firmly to pack it in.

For an extra touch of crunch, sprinkle crushed Nilla Wafers over the top before setting.

Let the treats cool at room temperature for about 1 hour.