Preheat the oven to 350°F (175°C) and grease a 9x13 inch (23x33 cm) baking pan.
In a medium saucepan, melt the unsalted butter over low heat, stirring occasionally.
Once melted, remove from heat and stir in granulated sugar until fully combined.
Add eggs one at a time, mixing well after each addition, then stir in the vanilla extract.
Sift together flour, cocoa powder, baking powder, and salt in a separate bowl.
Gradually fold the dry ingredients into the butter-sugar-egg mixture until just combined.
Gently fold in the semisweet chocolate chips.
Pour the batter into the prepared baking pan, spreading it evenly.
Bake in the preheated oven for 20-25 minutes, or until a toothpick inserted comes out with moist crumbs.
Allow the brownies to cool completely in the pan before cutting into squares.
