Yeah! That's the sort of thing I meant! lol
Your BMI is very acceptable, you are a healthy weight - what sort of weight do you want to gain?
Full size family cakes will line your arteries well, but if you have a fast metabolism it's unlikely to help you gain weight. You'd perhaps be better off trying to build up a little bit by eating a protein-rich diet? Have you always been a slim build or lost weight recently?