In a medium pot, heat your peanut butter and maple syrup on medium low. Stir until smooth and incorporated. Remove from burner and mix in the vanilla until incorporated. Next, mix in the rice puffs cereal until coated.
Line an 8x8 inch baking square with parchment paper. Transfer the mixture and tightly pack it into the pan with a silicone spatula.
Melt your chocolate chips on low heat, stirring constantly. Pour the melted chocolate onto the pan and spread out evenly. Optional: sprinkle with flaky sea salt. Place in your freezer, on an even surface, for 30 minutes. Remove from freezer allow 10 minutes to pass and then slice.