Step 1

Preheat oven to 350F, grease baking sheet or use baking mat.

Step 2

In a large bowl add butter, sugars and beat until light and fluffy. Add egg, vanilla extract and continue mixing. Add baking powder, baking soda, salt, mix, then add oats, rice krispies cereal, chocolate chips, marshmallows and mix with wooden spoon until combined. Then add flour and mix.

Step 3

Roll into balls and bake for 13 minutes or until golden brown.

Step 4

Allow to sit for 5 minutes on baking sheet, then transfer to cookie rack.