Quick fix is one egg beaten with a choc options or highlight and sweetner if v sweet tooth lol !! And place in micro for 1 min and serve hot with cold natural yougurt (free) with sweetner added always sorts the craving
I would either buy a cake or make a normal one and syn it - I've tried making diet cake and it just never tastes right, other than a low fat tea loaf recipe I tried but that doesn't sound like it's what you're after here
The WW cake bars are nice for 4 syns and you could have a slice of cake well within your syns as long as you are a bit careful and check the syns in the book or on the website. That's the joy of syns, no need to feel deprived or crave stuff that you can't have x