Beat the butter and caster sugar until pale and thick. Break the eggs into a bowl and mix with a fork, then gradually introduce into the butter and sugar, beating all the time. Add the self-raising flour, the spices, grated zest and the milk.
Pour the golden and maple syrups into the bowl, then spoon in the mixture and cover with a lid or baking parchment and foil or muslin, tied tightly with string or a rubber band.
Steam for an hour and half, leave for 10 minutes, then remove the lid or covering and loosen the sides with a palette knife. Turn out and serve with extra warmed maple syrup and double cream.