1. Heat the oven to 180C/160C fan/gas 4. Line a 20cm square tin with baking parchment. Melt the sugar and coconut oil in a pan over a medium heat, stirring regularly (the mixture will remain a little grainy). Remove from the heat and leave to cool for 10 mins.
2. Add 75g of the Dr. Oetker Extra Dark Chocolate Chunks to the pan and stir over a medium heat until melted. In a bowl, whisk the eggs and Dr. Oetker Vanilla Extract together, then add to the pan, stirring until smooth. Sift the flour, Dr. Oetker Baking Powder and Dr. Oetker Fine Dark Cocoa Powder into the pan, then fold together to make a smooth chocolatey batter. Transfer to the prepared tin and sprinkle with the remaining chocolate Dr. Oetker Extra Dark Chocolate Chunks.
3. Bake for 25-30 mins (the brownies should still be slightly wobbly in the centre), then leave to cool in the tin for 15 mins, before transferring to a cooling rack. Once cool, cut into 9 squares to serve – the brownies will keep in an airtight container for up to three days.