Preheat your oven to 350°F (175°C).

Line a 9x13 inch baking dish with parchment paper.

In a large bowl, cream together the softened butter and brown sugar.

Mix in the eggs and vanilla extract until smooth.

In a separate bowl, whisk together the flour, cocoa powder, baking soda, and salt.

Gradually add the dry ingredients to the wet mixture, stirring until just combined.

Gently fold in 1 cup of chocolate chips into the brownie batter.

In another bowl, cream together the granulated sugar, softened butter, and brown sugar for the cookie layer.

Mix in 2 eggs and 1 teaspoon of vanilla until combined.

In a separate bowl, whisk together the flour, baking powder, and salt for the cookie layer.

Gradually add the dry mixture to the cookie mixture, mixing until just combined.

Spread the brownie batter evenly in the prepared pan.

Dollop the cookie dough on top and gently spread it out.

Bake in the preheated oven for 25-30 minutes.

Let the brookies cool in the pan for about 15 minutes before lifting them out.

Slice into squares and serve.