Mix 5 cups of Oreo O’s® cereal and ½ cup mini marshmallows in a large mixing bowl and set aside.
Melt 6 tablespoons of butter.
Once the butter has melted, add in 4 cups of mini marshmallows and stir until mixture is smooth.
Combine Oreo O’s® cereal mix with marshmallow butter mix and stir until combined.
Add ¼ cups sprinkles and lightly fold into mixture.
Line and grease a 9 x 9 inch glass pan.
Pour mixture into pan and spread out evenly. Top with additional sprinkles to your liking.
Allow bars to harden for about 1 hour before cutting into 16 even squares. Remove from pan before decorating.
Decorate by melting 1 cup of blue candy melts (or white chocolate) and placing in a piping bag (or zip lock bag with the corner cut off). Drizzle melted candy over the top of the bars and top with additional sprinkles to your liking.