Preheat your oven to 350°F (175°C). Grease or line a 9x13-inch baking pan with parchment paper for easy removal of the brownies later.
Melt Butter and Chocolate:
In a medium saucepan over low heat, melt the butter and chopped chocolate together, stirring occasionally until smooth. Once melted, remove from heat and let it cool for a few minutes.
Mix Wet Ingredients:
In a large bowl, whisk together the granulated sugar, brown sugar, and eggs. Stir in the vanilla extract and then add the melted butter and chocolate mixture, whisking until fully combined.
Add Dry Ingredients:
Sift the flour, salt, and baking powder together in a separate bowl. Gradually fold the dry ingredients into the wet mixture, stirring just until combined. Avoid overmixing to keep the brownies soft and fudgy.
Fold in Chocolate Chips (Optional):
If desired, gently fold in the chocolate chips for an extra burst of chocolate in every bite.
Bake:
Pour the batter into the prepared baking pan and spread it out evenly. Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted into the center comes out with just a few moist crumbs (not wet batter).
Cool and Serve:
Let the brownies cool in the pan for at least 10 minutes before transferring them to a wire rack to cool completely. Once cooled, cut into squares and enjoy!