In a small bowl, combine flour, baking soda, sea salt, baking powder and cinnamon. Set aside. Do not add the oats to this step, they are added in later.
In the bowl of a standing mixer fitted with the paddle attachment beat together butter, peanut butter, brown sugar and granulated sugar until light and fluffy.
Once the monster cookie dough is finished, cover the bowl with plastic wrap, or transfer the dough to an airtight container with a lid and chill for at least 1 hour.