What tahini often tops (7)
I believe the answer is:
falafel
'what tahini often tops' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for falafel that I've seen before include "Deep-fried ball of ground chickpea" , "food item" , "vegetarian snack" , "Middle Eastern deep-fried ball of chick-peas etc" , "Cake of ground chickpeas" .)