Upper class peer essentially gets a jawbreaker perhaps (6)
I believe the answer is:
toffee
But I can't explain it at all! Could you help me understand?
(Other definitions for toffee that I've seen before include "That could be tough to swallow" , "Hard-to-chew sweet" , "can we not do something for it?" , "Sugar/butter sweet" , "Sweet made with heated butter and sugar" .)