Preheat the oven to 325 degrees Fahrenheit and line a large baking sheet with parchment paper.
In a bowl of a standup mixer cream together butter and brown sugar.
Add one egg and turn the mixer just to combine.
In a separate bowl whisk together flour, protein powder, baking powder, baking soda and salt.
Now add the flour mixture to the wet ingredients in the bowl and mix on low until dough forms. You may need to stop the mixer and scrape the bottom once or twice.
Finally, add oats and chocolate chips and mix a couple more seconds to combine.
Using a small cookie scoop or a tablespoon, drop 10 equally sized balls onto the prepared baking sheet.
Flatten each cookie using a wet spoon (they will spread but not much).
Bake for 13-15 minutes. Don't overbake or the cookies will be dry.
Cool the cookies on a rack for at least 15 minutes before enjoying.