Thoroughly grease bottom and sides of a 2 litre heat proof mould or 22cm ring cake tin. Sprinkle with white sugar and tap out excess.
In a large mixer bowl beat butter, sugar and vanilla until light and fluffy. Add eggs and blend well.
In separate bowl stir together flour, cocoa, cinnamon and bicarbonate of soda then add to butter mixture alternately with milk until well blended. Stir in the chopped nuts.
Spoon batter into the greased mould. Cover with a piece of greased aluminium foil, greased side down. Fold down edges of foil around rim; fasten securely with string.
Place a rack into a large saucepan and pour in water to top of rack. Heat water to boiling then place mould on rack. Reduce heat. Cover saucepan and steam cake over simmering water for an hour and 25 minutes or until cake tester inserted in centre comes out clean. (Add water, as needed, during steaming to keep water at rack level.)
Remove mould from the saucepan and cool 10 minutes on a cake rack. Run tip of sharp knife around edges then invert on serving plate. Serve hot accompanied with sauces of your choice.