Instructions

1. Line two baking sheets with parchment paper.
2. In a medium bowl, mix together the flour, cocoa powder, salt, and baking soda. Set aside.
3. To the bowl of an electric mixer, add the butter, sugar, and brown sugar. Mix on medium-high speed until light and fluffy, about 3-4 minutes. Scrape down the sides of the bowl with a rubber spatula. Add the egg and vanilla. Mix on medium until fully incorporated. Scrape down the sides again.
4. Add the dry flour mixture to the electric mixer and mix until just incorporated. Remove the bowl from the electric mixer and use a rubber spatula to gently fold in the chocolate chunks and popcorn.
5. Using a 2oz cookie scoop, scoop the cookie dough onto the prepared baking sheets, leaving at least 2 inches in between each cookie. Sprinkle sea salt flakes on the dough if desired. Refrigerate for at least 2 hours.
6. Preheat the oven to 350 degrees Fahrenheit.
7. Bake for 11 minutes, or until the edges of the cookies are just set and the middles still seem underdone. Cool completely on the baking sheets before removing to a plate.