You could swap the clem juice and zest for limes or oranges, you could add 2 tbsp of desiccated coconut to the cake batter along with some crystallised ginger pieces or some chopped hazelnuts, a shot of expresso in the cake batter and one in the pouring sauce would make a fab mocha dessert, some dried fruits or a chopped mango would work so well in the cake batter stage also.
The other thing I love about it is you make it up beforehand and cover and pop in the fridge. You can even make the day before so it's perfect if you have people over for supper. If you do make it please let me know especially if you try other flavours.
For the sponge
130g S/R flour
80g caster sugar
1 1/2 tsp baking powder
130 ml full fat milk
60g melted unsalted butter
Juice and zest of a clementine
2 eggs
30g cocoa
Preheat the oven to 170˚c
For the self saucing bit
200ml boiling water
50g Muscavado sugar
20g cocoa
Juice of a clementine
In a freestanding machine mix all of the above ingredients together, until smooth and creamy. Spoon into a buttered ceramic dish, cover with clingfilm and leave to rest in the fridge for at least 2 hours (If you don't rest for long enough the sauce will just combine with the sponge)