Coat a 8″ or 9″ cake pan with non-stick cooking spray. NOTE: The smaller the pan the thicker your layers will be.
Remove your ice cream from the freezer and place on your counter or in the sink for about 10 minutes to slightly thaw.
In a large non-stick pan, melt butter and mini mashmallows on low heat stiring regularly to ensure the mixture does not burn.
Slowly start to add rice krispie cereal into the mixture until well combined. Once mixed, turn off the heat.
Add half of the cereal mixture to your cake pan and press firmly into shape. NOTE: I always wet my hands a little bit to ensure the mixture doesn’t stick to them. Also, I try to ensure the two bottom and top layers of rice krispie are half the thickness of the ice cream layer. You are welcome to make them thinner or thicker based on your preference.
Cover your pan with a lid to keep the remaining mixture warm.
Place your baking pan with your first layer into the freezer for 10-5 minutes.
Remove the baking pan from the freezer and spread a thick layer of ice cream onto the bottom most layer of rice krispie cereal. Press firmly to ensure the ice cream layer is well compant and smooth at the top. As noted above, you can choose to layer one layer of ice cream, two or three side-by-side.
Place the baking pan back into the freezer for an additional 10-15 minutes.
Remove the baking dish from the freezer and layer the top layer of rice krispie cereal on top of the ice cream. Press firmly into shape. Place back into the freezer for 5+ hours or overnight.
Cut into squares or shapes and serve!