Making fudgy chewy brookies is straightforward and fun! Follow these steps for a delicious treat:

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Grease or line a 9×13-inch baking pan with parchment paper.
2. Prepare the Brownie Mixture: In a medium bowl, whisk together melted butter and granulated sugar until smooth. Add eggs and vanilla extract, mixing until well combined. Then stir in flour, cocoa powder, salt, and baking powder. Mix until just combined.
3. Make the Cookie Dough: In a large bowl, beat together the softened butter, granulated sugar, and brown sugar until fluffy. Mix in the egg and vanilla extract until smooth. In a separate bowl, whisk together flour, baking soda, and salt. Gradually add the dry ingredients to the butter mixture until fully blended. Fold in the chocolate chips.
4. Layer the Brownies and Cookies: Spread the brownie batter evenly into the prepared pan. Then, dollop spoonfuls of cookie dough over the brownie layer, spreading carefully to cover.
5. Swirl Together: Using a knife or spatula, swirl the cookie batter into the brownie batter for a marbled effect. Don’t overmix; leave some areas distinct.
6. Bake: Place the pan in the preheated oven and bake for 25-30 minutes or until a toothpick inserted in the center comes out with a few moist crumbs.
7. Cool: Once baked, remove from the oven and allow the brookies to cool in the pan for 10-15 minutes. Transfer to a wire rack to cool completely.
8. Slice and Serve: Once cooled, cut into squares or rectangles for serving.

These steps will guide you in creating fudgy chewy brookies that are sure to delight!