Preheat your oven to 350 degrees. Line your baking sheets with parchment paper or use these silicone baking mats.

In a large bowl, cream together your softened butter and sugars. Next add the eggs and vanilla and mix with your hand mixer. 

One by one, add the baking powder, salt, unsweetened cocoa and gluten free flour. User your hand mixer to to mix after each addition. 

Now it's time to add the gluten free rolled oats. Do not attempt to use your hand mixer. If you have a stand mixer, it may work, but I am not sure, as I do not have one. The best way I have found to mix the rolled oats in is to wash your hands and use your hands to mix it or wear food safe gloves. 

Chill your chocolate oatmeal cookie dough in the fridge for at least 40 minutes.

Using a cookie scoop, place your cookie dough on the parchment paper or silicone baking mats. Bake for 9-11 minutes. 9 minutes will give you an amazing chewy cookie. If you like a crunchy outside with a chewy inside, bake for 10 or 11 minutes.  Allow the cookies to cool on the baking sheet for about 5-7 minutes before transferring to a wire rack.