Cook's cake had exotic fruit toppings (4)
I believe the answer is:
chef
'cook's' is the definition.
(chef is a kind of cook)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for chef that I've seen before include "Professional cook" , "who has a set of knives?" , "Originator of courses" , "Cooker?" , "member of kitchen staff" .)