Preheat the oven to 350
Line 8*8 baking dish with parchment paper or spray with non stick baking spray and set aside.
In a medium sized bowl, melt the butter in 15 second increments (so it doesnt explode) until fully melted
Add in granulated sugar to melted butter and whisk to combine.
Next add in the eggs and vanilla. Whisk until incorporated.
Sift in the dry ingredients: cocoa powder, salt and flour.
Stir brownie mix using a rubber spatula.
Add in 1 1/2 cup of the chocolate (chips, chunks or chopped pieces) and fold together with the rubber spatula.
Pour brownie batter into the baking dish.
Add the remaining chocolate to the top and lightly press into the mixture.
Bake for 25-30 mins (until the edges are set and a toothpick comes out with a few crumbs but no batter)
Allow to cool completely, then slice and serve.