Discover gold under a dish on the mesa (7)
I believe the answer is:
plateau
'the mesa' is the definition.
(thesaurus)
'discover gold under a dish on' is the wordplay.
'discover gold under' becomes 'au' (I am not sure about this - if you are sure you should believe this answer much more).
'a dish' becomes 'plate' (plate is a kind of dish).
'on' says to put letters next to each other.
'au' put after 'plate' is 'PLATEAU'.
Can you help me to learn more?
(Other definitions for plateau that I've seen before include "High flat land" , "Raised level area" , "somewhere flatter?" , "Area of livel high ground" , "Large level tract of elevated land" .)