I don't have any sr flour either but i do have a 'never fail sponge cake' recipe that i have used twice now.
I do have cadbury's drinking chocolate though.
Will that not do???
Never have understood why it has to be cocoa powder.
Going to top them and put butter cream in them. (possibly chocoaltey too)
Or if anyone is driving past my house would they like to get some and drop it off to me???