Melt butter and mix Marshmallows together. Either on medium on the stove top. Or in 30 second increments in the microwave.
Once melted, add and stir in the blue food coloring
Add and stir in Rice Krispies cereal. Make sure that mixture is evenly distributed.
Spread mixture into pan with greased spatula.
Cool treats for 30 mins, cut, and enjoy!