Preheat Your Oven and Prepare Baking Sheets: Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper or silicone baking mats.
Melt the Butter and Chocolate: In a heatproof bowl, combine the butter and dark chocolate. Melt them together over a double boiler or in the microwave (in 30-second intervals, stirring in between) until smooth. Set aside to cool slightly.
Mix the Dry Ingredients: In a medium bowl, whisk together the flour, cocoa powder, salt, and baking powder. This ensures even distribution and prevents clumps.
Beat the Wet Ingredients: In a large mixing bowl, combine the sugar, brown sugar, eggs, and vanilla extract. Use an electric mixer to beat on medium speed for about 7 minutes until the mixture is thick and pale. (Don't skip this step it's critical if you want the glossy cracked top on the cookies.)
Combine Chocolate Mixture with Wet Ingredients: Slowly pour the melted chocolate and butter mixture into the wet ingredients while mixing on low speed. Blend until smooth and glossy.
Incorporate the Dry Ingredients: Gradually add the dry ingredients into the chocolate mixture, mixing on low speed until just combined. Be careful not to overmix.
Chill the Dough (Optional but Recommended): If the dough feels too soft, refrigerate for 20–30 minutes to make it easier to scoop and bake.
Scoop and Arrange on Baking Sheets: Use a cookie scoop or heaping tablespoon to portion the dough onto the prepared baking sheets, leaving about 1½ inches of space between each cookie.
Add Optional Topping: If desired, sprinkle a pinch of flaky sea salt on top of each cookie for a delightful contrast to the rich chocolate flavor.
Bake: Bake in the preheated oven for 10–12 minutes, or until the edges are set but the centers still look slightly soft.
Cool and Serve: Allow the cookies to cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely. Enjoy your Brookie Bliss warm or at room temperature!