Step: 1/10

Weigh and arrange all ingredients for use.

Step: 2/10

In a pan, melt the dark chocolate with the butter over a low heat, stirring.

Step: 3/10

Mix the sugar, salt and vanilla sugar in a bowl and stir in the melted chocolate.

Step: 4/10

Gradually beat in the eggs.

Step: 5/10

Mix everything until smooth.

Step: 6/10

Sieve in the flour and cornflour and fold into the chocolate mixture.

Step: 7/10

Preheat the oven to 180°C (160°C fan, gas 4). Line a cake tin with baking paper. Spoon the chocolate mixture into the tin and spread level.

Step: 8/10

Scatter over the chocolate chips.

Step: 9/10

Bake in the oven for about 25 minutes. The cake should still be slightly crusty on top but still slightly moist inside. Allow to cool completely.

Step: 10/10

Turn out the brownie and cut into pieces.