Chop the chocolate into chunks.

Pre heat the oven to 180°C.

Line the baking tray with parchment paper.

Fit the K beater to the machine.

Add Ingredients 1 (sugars, butter, vanilla) into the Mixer bowl.

Attach the Mixer bowl to the machine and fit the splash guard.

Mix on speed 3 for about 2 minutes.

Sift the first 2 items of Ingredients 2 (flour, cocoa powder) into the large bowl.

Add the rest of Ingredients 2 (bicarbonate of soda, salt) to the bowl.

Mix until combined.

Transfer contents of the large bowl to the Mixer bowl.

Mix on speed 2 for about 2 minutes until combined.

Add Ingredients 3 (milk) into the Mixer bowl.

Mix on speed 2 for about 1 minute.

Add Ingredients 4 (chocolate) into the Mixer bowl.

Mix on speed 2 for about 1 minute.

Roll the mixture into small balls and place on the baking tray leaving enough room for the cookies to spread.

Bake for 10 minutes at 180°C.

Let cool.

Serve.