Preheat your oven to 350°F. Line two baking sheets with parchment paper and set them aside.

In a stand mixer with a paddle attachment, cream the butter and sugars on medium-high until light and fluffy, about 3-4 minutes. Add the egg and vanilla, mixing until well combined.

Blend oats in a blender or food processor until you have a mix of oat flour and larger oat pieces (you can chop them with a knife if preferred).

Incorporate the baking soda, salt, flour, and oats into the butter mixture, mixing until just combined.

Gently fold in the rice krispie cereal and both types of chocolate.

Form dough into large balls using a ¼ cup cookie or ice cream scoop. Place them on the prepared baking sheets, topping each ball with extra chocolate pieces and a sprinkle of flaked sea salt.

Bake for 11-13 minutes. If desired, sprinkle a bit more sea salt on top after baking.