Condiment and perfect herb (10)
I believe the answer is:
peppermint
'herb' is the definition.
(peppermint is a kind of herb)
'condiment and perfect' is the wordplay.
'condiment' becomes 'pepper' (I've seen this before).
'and' means one lot of letters go next to another.
'perfect' becomes 'mint' ('mint' can be similar in meaning to 'perfect').
'pepper'+'mint'='PEPPERMINT'
(Other definitions for peppermint that I've seen before include "flavour" , "Sweet flavoured with aromatic oil" , "Pungent sweet" , "Aromatic plant" , "herb" .)