Ancient city in Jordan, one favoured by artist (5)
I believe the answer is:
petra
'ancient city in jordan' is the definition.
(I've seen this in another clue)
'one favoured by artist' is the wordplay.
'one favoured' becomes 'pet' (as in a pet project).
'by' says to put letters next to each other.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'pet'+'ra'='PETRA'
(Other definitions for petra that I've seen before include "Jordan's rock-hewn city" , "Picturesque city" , "Old city in Jordan" , "Rock-hewn city of Jordan" , "Long-lost city of Jordan rediscovered in 1812" .)