At last I have something to eat! (6)
I believe the answer is:
endive
'something to eat' is the definition.
(endive is a kind of food)
'at last i have' is the wordplay.
'at' means one lot of letters go next to another.
'last' becomes 'end'.
'i have' becomes 'ive'.
'end'+'ive' is 'ENDIVE'.
(Other definitions for endive that I've seen before include "Portion of salad" , "Plant used in salads" , "Salad plant related to chicory" , "Type of chicory" , "Veined (anag) - salad plant" .)