Pulse found in the cooking of broth (5)
I believe the answer is:
throb
'pulse' is the definition.
(I know that pulse can be written as throb)
'cooking of broth' is the wordplay.
'cooking of' indicates an anagram (I've seen 'cooking' mean this (cook can mean to falsify or distort)).
'broth' is an anagram of 'THROB'.
'found in the' acts as a link.
(Other definitions for throb that I've seen before include "Drum" , "Sound of engines" , "Pulse" , "One's heart may do it" , "Vibrate with rhythm like heart" .)