Step 1

Preheat oven to 350 degrees. Line a square 9x9" baking dish with a parchment paper sling or spray with baking spray.

Step 2

In a large microwave-safe bowl, combine the bittersweet chocolate and butter. Microwave on high in 20-30 second bursts, stirring well between bursts of heat until melted and smooth. Whisk in cocoa powder.

Step 3

Add granulated sugar and brown sugar, whisking well to combine. Add eggs and vanilla, beating well either by hand with a whisk or using an electric mixer.

Step 4

Sprinkle the flour and salt over the brownie batter and gently stir it in with a wooden spoon or spatula. Stir in chocolate chips.

Step 5

Pour the brownie batter into the prepared baking dish and spread into the corners. The batter will be thick.

Step 6

Bake for 30 to 35 minutes, until a toothpick inserted into the center of the brownies comes out mostly clean with only a few crumbs attached. Be sure not to overbake.

Step 7

Cool completely before cutting. Store in an airtight container for up to 5 days on the counter or in the fridge.