Preheat your oven to 350°F (175°C). Grease and line a 9x13 inch baking pan with parchment paper, leaving some overhang for easy removal.
In a large mixing bowl, combine the melted butter, granulated sugar, and brown sugar. Whisk until smooth and well combined.
Add in the eggs one at a time, whisking well after each addition. Stir in the vanilla extract.
In a separate bowl, sift together the flour, cocoa powder, baking powder, and salt. Gradually fold this dry mixture into the wet ingredients using a spatula. Be careful not to overmix.
Gently stir in the chocolate chips until evenly distributed. Pour the brownie batter into the prepared baking pan and smooth the top with a spatula.
Bake for 25-30 minutes or until a toothpick inserted in the center comes out with a few moist crumbs. Let the brownies cool completely in the pan on a wire rack.
While the brownies are cooling, prepare the ganache. In a small saucepan, heat the heavy cream over medium heat until it just starts to simmer.
Remove from heat and add the chopped chocolate and butter. Let it sit for a minute, then whisk until smooth and glossy.
Once the brownies are completely cooled, carefully remove them from the pan using the parchment paper. Cut into squares and drizzle the chocolate ganache over the top.
Optionally, sprinkle some sea salt on top of the ganache for a touch of contrast in flavor.
Notes
For an extra touch, sprinkle sea salt on top of the ganache.