Pre-heat the oven to 175°C (350°F) and grease/line a 18cm / 7" pan.
Melt the butter and allow to cool for a couple of minutes.
Using a food processor (or electric whisk), mix the butter, eggs, milk, cream and coffee mixture until well combined.
In a separate bowl, combine the sugar, flour, cocoa powder, baking powder, and baking soda.
Add to the wet ingredients and mix until everything is combined.
Pour the batter into the prepared pan and bake for around 40 minutes, until the edges start to pull away from the pan and an inserted skewer comes out clean. If you find the top is browning too much, just cover with a sheet of foil.
Remove from the oven and allow the cake to cool for a while in the pan before turning out onto a wire rack. Allow it to cool completely before decorating.