Preheat the oven to 350°F (175°C).
In a separate bowl, mix the rice crispy cereal, oats, and coconut flakes and set aside.
Sift the flour, baking soda, baking powder, and salt into another bowl and set it aside.
In a large mixing bowl, cream together the brown sugar, white sugar, butter, eggs, and vanilla extract until smooth.
Gradually add the flour mixture to the creamed mixture, mixing until just combined.
Stir in the oatmeal mixture.
Using your hands (make sure they are clean), form the dough into balls and place them onto a baking sheet.
Bake in the preheated oven for 10-12 minutes or until the edges are lightly golden. If you prefer a softer cookie, reduce the baking time.