Set your oven to 350°F (175°C). While it's warming up, grease a 9x9-inch baking pan or line it with parchment paper for easy removal later.

In a microwave-safe bowl or over low heat on the stovetop, melt the butter. Allow it to cool slightly before using it in the batter.

In a large mixing bowl, whisk together the sugar, eggs, and vanilla extract. Mix until smooth and well combined, creating a light, airy texture.

Pour the melted butter into the sugar-egg mixture, stirring gently to combine. The butter should be cool enough that it doesn't cook the eggs when added.

Sift in the cocoa powder, flour, salt, and baking powder into the wet ingredients. Stir the mixture gently until just combined—be careful not to overmix.

For extra chocolatey goodness, fold in chocolate chips. This step is optional but highly recommended for anyone craving even more chocolate flavor!

Transfer the brownie batter into your prepared baking pan. Use a spatula to spread it evenly across the pan.

Place the pan in the preheated oven and bake for 20-25 minutes. Start checking at the 20-minute mark. The brownies are done when a toothpick inserted into the center comes out with a few moist crumbs, not wet batter.

Let the brownies cool in the pan for 10-15 minutes before transferring them to a wire rack to cool completely. Once cool, cut them into squares and serve.