The light breakfast carried up does come as a surprise (7)
I believe the answer is:
stagger
'a surprise' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for stagger that I've seen before include "Teeter" , "Walk as though in danger of falling" , "bowl over" , "Reel; arrange so as to be out of line" , "Reel; amaze" .)