Preheat the oven to 350°F (175°C). Layer a standard oven-size baking tray with parchment paper.
In a pot melt together 9 oz (250 g) of chocolate with butter. Set aside. Chop the remaining 2 oz (50 g) of chocolate and set aside.
In a separate bowl combine flour, baking powder, salt, cocoa powder and espresso powder.
In a stand mixer fit with a whisk attachment (or a hand mixer), whip the eggs and both sugars. Whisk on high speed for 2-3 minutes until light and fluffy. It's important to whip the butter and sugars this long to get the crinkly top that you know and love in a brownie.
Add the flour mixture to the egg mixture. Change the mixer attachment to paddle attachment. Mix on low speed just until combined. Scrape down the sides of the bowl.
Fold in the cooled chocolate and butter mixture, mix on low speed just until incorporated. Add the remaining, chopped chocolate and fold everything together.
Using a standard size cookie scoop or an ice cream scoop, scoop out the cookies onto the baking sheet, dropping them approximately 2 inches (5 cm) apart. Bake for 10 minutes at 350°F (175°C).
Sprinkle the cookies with some flaky salt for garnish if desired. Let the cookies cool on a wire rack and ENJOY!
Notes
*Ghirardelli or Lindt bars work great for this.Refer to the article above for more tips and tricks.The calories shown are based on the cake being cut into 9 pieces, with 1 serving being 1 slice of cake. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information. The information in the nutrition box are calculated through a program and there is room for error. If you need an accurate count, I recommend running the ingredients through your favorite nutrition calculator.**