Melt the butter and chocolate in a medium microwave safe bowl in 30 second increments, stirring after each, in the microwave. Remove from the heat, pour into a large mixing bowl, and allow to slightly cool.

Whisk the granulated and brown sugars into the cooled chocolate/butter mixture. Add the eggs, one at a time, whisking until smooth after each addition. Whisk in the vanilla. Gently fold in the flour, cocoa powder, and salt. Once combined, fold in the chocolate chips.

Preheat oven to 175C. Line the bottom and sides of a 8x8 inch square baking pan with parchment. Pour batter into the prepared pan and bake for 30-35 minutes or until the brownies begin to pull away from the edges of the pan. A toothpick inserted in the center should come out with only a few moist crumbs when the brownies are done.