In a large mixing bowl, mix sugar and cocoa powder together.
2 Cups Sugar, 2/3 Cup Cocoa Powder
Mix in the melted butter, eggs, and vanilla until smooth.
1 Cup Butter, 4 Large Eggs, 2 teaspoons Vanilla
Add the flour and salt and mix until just combined.
1 1/2 Cup Flour, 1/2 teaspoon Salt
Spread into the greased pan.
For the Cookie
Cream the butter and sugars together for 2 minutes and then mix in the egg, egg yolk, and vanilla.
10 Tablespoons Butter, ⅔ Cups Brown Sugar, ⅓ Cup White Sugar, 1 Egg + 1 Egg Yolk, 1 teaspoon vanilla
Add the dry ingredients and mix until combined.
1⅔ Cup Flour, ¾ teaspoon Baking Soda, ¾ teaspoon Salt
Use a wooden spoon to mix in chocolate chips.
Scoop out spoonfuls of dough, flatten with your hands and piece together over the brownie batter (or you can put all the dough between two layers of plastic wrap, roll out, and then place over batter).
Sprinkle more chocolate chips on top if desired.
1 Cup Chocolate Chips
Bake for 35-40 minutes or until cookie is golden, tenting with foil if the top is getting too brown.
Let the brookies cool completely before cutting.
Notes
Brookie bars will keep for 3 days in an airtight container, or can be frozen for up to 3 months.