Type of sauce produced by head, head of restaurant (5)
I believe the answer is:
caper
'type of sauce' is the definition.
'by head head of restaurant' is the wordplay.
'by' is a charade indicator (letters next to each other).
'head' becomes 'cape' (I've seen this before).
'head of' suggests taking the first letters.
The first letter of 'restaurant' is 'r'.
'cape'+'r' is 'CAPER'.
'produced' is the link.
(Other definitions for caper that I've seen before include "Leap about" , "Something in the sauce" , "Escapade with an edible bud?" , "Frisk" , "Skip/dance about" .)