1. Grease a 9×13 pan, set aside

Caramel Filling

1. In a large microwave safe bowl combine caramel pieces, sweetened condensed milk and 1/2 cup butter. Microwave on high in 1 minutes increments (stirring after each) until caramels are melted, approx 3-4 minutes.
2. Stir until smooth, set aside.

Krispie Treats

1. Take 6 Tbsp butter and 4 cups marshmallows. Heat in microwave for 1 minute, stir, repeat if necessary in 20 second increments until marshmallows are melted. Stir until butter and marshmallow are combined.
2. Pour 5 cups Krispie Rice Cereal into marshmallow mixture, stir until coated. Press into the bottom of prepared pan.
3. Pour caramel over top Krispie layer and then sprinkle 2 cups mini marshmallows on top of that.
4. Refrigerate for 20 minutes until caramel has set.
5. When caramel has set repeat the krispie layer (step 4) with remaining ingredients. Press final krispie layer on top of caramel.
6. * TIP ~ Spray a piece of parchment or wax paper lightly with cooking spray and press the krispies lightly and evenly into pan.
7. Let krispies set up for at least 2 hours before cutting into squares. The caramel layer takes a bit of time to set up.