Preheat the oven to 160°C / 320°F (fan/convection) or 180°C / 355°F (standard). Grease and line a 20 cm (8 inch) circular cake tin with baking paper.
In a large mixing bowl, whisk together milk and vinegar. Allow to sit for 5 minutes until thickened. Whisk in oil, eggs, brown sugar and caster sugar.
Sift over flour, cocoa powder, baking powder and salt. Whisk together until well combined. Whisk in boiling coffee (or water).
Pour into prepared tin and place in the lower half of the oven. Bake for 55-60 minutes or until well risen and a skewer inserted in the centre of the cake comes out clean (don’t open the oven until at least the 45 minute mark). The top may crack slightly but it will sink back down once the cake cools. Allow to cool in the tin for 20 minutes before transferring to a wire rack to cool completely.
Notes
Storage
