In kind of tart, it ruined taste at first (3,3,3)
I believe the answer is:
tit for tat
'in kind' is the definition.
(both can describe a fair exchange)
'of tart it ruined taste at first' is the wordplay.
'ruined' indicates an anagram.
'at first' says to take the initial letters.
The initial letter of 'taste' is 't'.
'of'+'tart'+'it'='oftartit'
'oftartit' anagrammed gives 'titforta'.
'titforta'+'t'='TIT-FOR-TAT'
(Other definitions for tit for tat that I've seen before include "An eye for an eye" , "protection given to Barnet" , "Retaliation for an injury - almost equal" , "reprisal" , "Equivalent retaliation" .)