In a big pot, melt the butter without salt over low heat.
After the chocolate is melted, put in the small marshmallows and keep stirring until they are completely melted and smooth.
Take the pan off the stove and add the Rice Krispie cereal.
Use a spatula or wax paper to mix the cereal with the marshmallow mixture until everything is well covered.
Press the layer of Rice Krispies for 2 minutes.
Put oil or butter on a baking dish that measures 9 by 13 inches.
Spread the Rice Krispie mixture evenly in the pan. You can use a spatula or wax paper to spread and press down the mixture.
Allow the Rice Krispie layer to cool down and harden completely at room temperature.
Make the banana pudding layer (3 minutes):
