Spray a 8 x 8 square pan with cooking spray.
In a large pot, on medium heat, melt butter and add 4 cups of mini marshmallows. Stir until melted.
Remove from heat and stir in rice cereal and then remaining 2 cups of mini marshmallows.
Press ½ of mixture into the prepared pan. Drop spoonfuls of Nutella on top of cereal mixture.
Press remaining cereal on top of nutella and sprinkle with chocolate sprinkles.
Enjoy!!!