Prepare the pan – Preheat oven to 350°F (175°C). Line an 8x8 baking dish with parchment paper, leaving some overhang on the sides for easy lifting.

Brown the butter – In a small saucepan over medium heat, melt the butter. Continue cooking until it turns golden brown and gives off a nutty aroma. Immediately remove from heat to prevent burning.

Melt chocolate – While the butter is still hot, pour it over the chocolate chips in a large mixing bowl. Stir until the chocolate is fully melted and smooth.

Add sugars and salt – Whisk in the white sugar, brown sugar, and salt until combined.

Beat in eggs – Add the eggs one at a time, whisking well after each addition. Continue whisking for about 2 minutes until the mixture looks shiny and thick—this step helps create the signature crinkly top.

Add vanilla – Stir in the vanilla extract.

Fold in dry ingredients – Sift the cocoa powder and flour directly into the bowl. Gently fold with a spatula until just combined, being careful not to overmix.

Bake – Pour the batter into the prepared pan and smooth out the top. Bake for 35–40 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs (not wet batter).

Cool and serve – Let the brownies cool completely in the pan before lifting them out with the parchment paper. Cut into 9 squares and enjoy the fudgy centers with their delicate crinkly tops.