Start by preheating your oven to 350°F (180°C). Line a 9x9-inch square baking pan with parchment paper, making sure to leave some extra hanging over the edges. Spraying a bit of non-stick spray underneath the parchment helps keep it in place and saves you from any sticky situations.

To evenly blend, sift the flour, cocoa powder, baking powder, and salt into a mixing bowl. Once sifted, give everything a quick whisk to blend it well, this ensures your brownies come out smooth and lump-free.

In a microwave-safe bowl, melt the butter and chopped dark chocolate together until fully combined. Heat in short bursts of 30 seconds, stirring each time until fully melted and silky smooth. Generally, this process takes around a minute.

Add the sugars, buttermilk, vanilla extract, and a small pinch of espresso powder to the melted chocolate mixture. Whisk everything together until smooth.

Combine the wet ingredients with the dry mixture in the same bowl. Using a spatula or large spoon, gently fold everything together until you have a thick, glossy batter. Be careful not to overmix.

Gently mix in the chocolate chips, setting aside a handful for topping. This little topping step gives your brownies that bakery-style look and extra bursts of chocolate.

Spread the batter evenly in the prepared pan after transferring it in. Give the pan a gentle tap on the counter to smooth the surface. Bake for about 35 minutes, or until the top is set and has a slight shine.

Let the brownies rest in the pan for 10 minutes once they’re out of the oven. Then lift them out. For the best fudgy texture, allow the brownies to cool completely before slicing. Enjoy!