Melt the chocolate and butter

• Melt the chopped dark chocolate with the butter in a saucepan over low heat until smooth.
• Remove from the heat and let cool slightly.

Preheat the oven

• Preheat the oven to 180 °C and line a square cake pan with baking paper.

Whisk the sugars and eggs

• Whisk the granulated sugar, brown sugar and eggs in a mixing bowl until pale and thick.
• Stir in the vanilla extract.

Combine the batter

• Fold the melted chocolate mixture into the egg mixture.
• Sift in the flour, cocoa powder and salt, then fold gently until just combined.

Bake the brownies

• Pour the batter into the prepared pan and smooth the top.
• Bake until the top is crinkled and a toothpick comes out with moist crumbs.

Cool and slice

• Let the brownies cool completely in the pan before slicing into squares.