To create a perfect crackly top on your brownies you need to do one thing. Beat your eggs well! I found beating each full egg for an entire minute creates that crackly top. You’re basically creating a meringue when you do this and during baking the crystalized parts will form on top giving you that shiny, shattery crust everyone loves. 

INGREDIENTS Cooking spray 3/4 c. all-purpose flour 2 tsp. espresso powder 1 tsp. kosher salt 4 c. dark chocolate chips, divided 1 c. (2 sticks) butter, cut into large chunks 1 1/3 c. granulated sugar 4 large eggs 2 egg yolks

DIRECTIONS

1. Preheat oven to 350°. Line a 9”-x-13” baking pan with parchment paper and grease with cooking spray. In a small bowl, whisk together flour, espresso, and salt. 
2. Set a large heat-proof bowl over a saucepan of simmering water to create a double-boiler. Add 3 cups chocolate chips and butter to bowl. Stir occasionally until melted together. Remove bowl from heat, then whisk in sugar. 
3. Add eggs one at a time, whisking for 1 minute after each egg, then add egg yolks and whisk for 1 minute more. Fold in flour mixture just until combined, then fold in remaining 1 cup chocolate chips. 
4. Pour batter into prepared pan and smooth top. Bake until a toothpick inserted in middle comes out with a few moist crumbs, 28 to 30 minutes. Let cool in pan for 30 minutes before using parchment paper to remove from pan.