Mix crispy rice cereal, oat cereal rings, sunflower seeds, raisins, and chocolate chips together in a large bowl.
Stir honey and brown sugar in a saucepan, place over high heat, and bring to a boil. Stir and boil for 1 minute. Remove from heat and stir in peanut butter and vanilla extract until smooth and well blended.
Pour the hot peanut butter mixture into the dry ingredients and stir until all dry ingredients are moistened.
Press the mixture into the prepared baking dish to make an even layer.