I agree. I can find no reference to it in Chambers as either one or two words. Perhaps it is a newish word meaning to sprinkle, hot being fresh and pepper the powerful ingredient. Seems to be the only thing that will fit, though.
Guys, if it helps, I have had the same dilemma - it is the final clue too!
I have decided to go with it although I, too, am uncomfortable with it as a single word. We'll know soon enough... JVW