Preheat the oven to 350F. Prepare a 12 cup bundt pan by brushing it with melted butter.
Sieve the flour, cocoa powder, baking powder, bicarbonate of soda and salt into a large mixing bowl.
Use a whisk to mix together then and the brown sugar and mix again. Make a well in the center.
In a separate bowl or jug, mix together the eggs, canola oil, soured cream and coffee.
Slowly pour the wet ingredients into the dry ingredients beating well as you go.
Transfer the cake batter into the bundt pan, the mixture will look very thin and runny. The mixture will fill the tin to two-thirds full.
Bake in the center of the preheated oven for 25 minutes
Leave to cool in the bundt pan for 10 minutes before inverting on to a cake stand or wire rack. Leave to cool completely before frosting.