Brown the butter

• Melt the butter in a saucepan over medium heat and cook until golden brown and nutty.
• Pour into a bowl and let it cool slightly.

Mix the wet ingredients

• Whisk the brown sugar and granulated sugar into the brown butter.
• Add the eggs and vanilla and whisk until smooth and glossy.

Add the dry ingredients

• Sift in the flour, cocoa powder, salt and baking soda.
• Fold gently until just combined, then fold in the chocolate chips.

Bake the brownies

• Pour the batter into a lined baking dish and spread evenly.
• Bake at 180 °C until the top is set and a toothpick comes out with moist crumbs.

Cool and cut

• Let the brownies cool completely in the dish.
• Cut into squares and serve.