Bitter type from kitchen garden envied cook (6)
I believe the answer is:
endive
'bitter type from kitchen garden' is the definition.
The definition and answer can be both things that one consumes for nourishment as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'envied cook' is the wordplay.
'cook' indicates an anagram.
'envied' with letters rearranged gives 'ENDIVE'.
Can you help me to learn more?
(Other definitions for endive that I've seen before include "Plant used in salads" , "Salad plant with crisp curly leaves" , "Salad plant related to chicory" , "Envied the salad green badly" , "Type of chicory" .)