Preheat and prepare the pan

• Preheat the oven to 170 °C.
• Line a square baking pan with parchment paper.

Melt the butter and chocolate

• Melt the butter and chopped chocolate together in a saucepan over low heat.
• Let the mixture cool slightly.

Whisk the sugars and eggs

• Whisk the brown sugar, white sugar and eggs until thick and glossy.
• Add the vanilla extract and mix well.

Combine the chocolate mixture

• Pour the melted chocolate mixture into the egg mixture.
• Stir until fully combined.

Fold in the dry ingredients

• Sift in the flour, cocoa powder and salt.
• Gently fold until no dry streaks remain.

Add the chocolate and fill the pan

• Fold in the chocolate chunks and chocolate chips.
• Spread the batter evenly into the prepared pan.

Decorate the top

• Scatter Christmas sprinkles and extra chocolate pieces over the batter.

Bake the brownies

• Bake until the edges are set and a toothpick inserted in the center comes out with moist crumbs.

Cool and slice

• Let the brownies cool completely in the pan.
• Slice into squares for a rich, fudgy texture.