Preheat your oven to 350°F (175°C). Grease an 8x8-inch square baking pan or line it with parchment paper for easy removal.
In 20 second intervals melt butter in the microwave until liquid. Add in your chopped chocolate and stir until melted.
In a medium bowl, combine your eggs, sugars, and vanilla extract. Beat the mixture on high until lightened in color and thickened and fluffy in texture.
On low speed, gradually pour the chocolate mixture.
Use a rubber spatula to stir in flour, cocoa powder, baking powder and salt until just combined. Stir in the chocolate chips.
Pour into prepared pan and smooth out . Bake in oven for 22 to 25 minutes, or until set but not overbaked. Let cool in pan completely before slicing and serving.
