01 -
Preheat oven to 350°F (175°C). Line a metal 8-inch square pan with parchment paper.
02 -
In a large microwave-safe bowl, combine the chopped semisweet chocolate and unsalted butter. Microwave in 30-second intervals, stirring between each burst, until melted and smooth.
03 -
Add granulated sugar to the hot butter-chocolate mixture and whisk vigorously until combined. Let cool until just barely warm.
04 -
Mix in the eggs, egg yolk, and vanilla extract. Whisk for about 1 minute until very well combined to help create a shiny crust on top.
05 -
Use a rubber spatula to stir in the all-purpose flour, unsweetened cocoa powder, and fine salt until just combined. Stir in the semisweet chocolate chips.
06 -
Pour the batter into the prepared pan and smooth out the top. Bake in the preheated oven for 25 to 30 minutes, or until a toothpick inserted into the center comes out with moist crumbs.
07 -
Allow the brownies to cool in the pan for 30 minutes before slicing.