Creating the Best Fudgy Chewy Brookies involves the following steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Grease a 9×13 inch baking pan or line it with parchment paper for easy removal.
2. Prepare the Cookie Dough: In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until fluffy.
3. Add Eggs and Vanilla: Mix in the eggs, one at a time, followed by the vanilla extract, blending until combined.
4. Incorporate Dry Ingredients: In a separate bowl, whisk together the all-purpose flour, baking soda, and salt. Gradually add the dry ingredients to the wet mixture until just combined. Stir in chocolate chips if using.
5. Spread Cookie Dough: Use a spatula to evenly spread the cookie dough into the prepared baking pan, creating a smooth layer at the bottom.
6. Prepare the Brownie Batter: In another mixing bowl, combine the melted butter and granulated sugar until well combined. Add the eggs and vanilla, mixing well.
7. Mix in Dry Ingredients: Sift in cocoa powder, flour, and salt, and stir until the batter is smooth. Add chocolate chips if desired.
8. Spread Brownie Batter: Carefully pour the brownie batter over the cookie layer, making sure to spread it evenly.
9. Bake: Place the pan in the preheated oven and bake for 25-30 minutes or until a toothpick inserted in the center comes out mostly clean (a few moist crumbs are fine).
10. Cool & Cut: Allow the brookies to cool in the pan for about 10-15 minutes before cutting them into squares. Enjoy!