Orange cake - orange or lemon icing?

[CleanHankie]

I agreed this morning to make some sponges for my mother for tomorrow morning. I've got an orange sponge in the oven but realised I don't have enough orange juice to make the icing (having just thrown the orange I grated for the sponge into the bin). Do you think it would be ok to be filled with lemon curd and topped with lemon icing? Or shall I pop into the corner shop during the school run later, for an orange?

Sounds lovely: 'citrus special'.

I used to love icing made with lemon juice. TBH orange really doesn't quite cut it.

Mmmmm sounds lovely!