Personally, I think about food if I'm trying to not cum The thought of mushrooms really is off putting.
When you're getting a bit too excited a bit too prematurely, a favourite solution of my own is "Granny having a ****e, Granny having a ****e, Granny having a ****e"
I tried that one, but I tried mushrooms and it moved on to a fry up. A minute later I was bored of sex and got hungry.
I can give it out, but it's not worth it if you've no ****ing rep coz it doesn't make a jot of a difference