- Preheat your oven to 350°F and prepare a standard 9×13″ baking pan by lining with parchment paper or spraying with cooking oil. 
- Melt the butter in a microwave safe bowl in 30 second increments until the butter is fully melted. Next, stir in the granulated sugar and mix for 2-3 minutes until fully combined. 
- Slowly mix in the eggs, one at a time. Make sure each egg is fully incorporated before moving on to the next one. Then mix in the vanilla extract and salt. 
- Add in the flour and cocoa powder and mix until well-combined. Carefully fold in the chocolate chips and make sure they are spread evenly throughout the batter. 
- Pour the batter into the prepared baking pan and set aside. 
- To begin the cookie layer, cream the butter and sugar together in a large bowl with your electric or stand mixer until it is light and fluffy***.  
- Add in the egg and vanilla extract and beat the mixture well. 
- In a separate medium bowl, whisk together the flour, baking soda, and salt. 
- Carefully add the dry ingredients from the medium bowl to the wet ingredients in the large bowl. Take your time and mix in the dry ingredients slowly. Then, mix until a consistently soft dough forms. Finally, carefully mix in the chocolate chips. 
- Scoop out the dough into rounded balls using a dough scoop, a spoon, or your hands. Grab the brownie pan from earlier. Drop the rounded cookie dough over the brownie layer, leaving some gaps in between. 
- Bake @ 350°F for 25-30 minutes, or until the cookie dough areas are golden brown and the brownie layer is set. Carefully, remove the brookies from the oven and allow them to cool ~ 10-15 minutes before cutting into pieces for serving.