Two suggestions that may work:
Feijoa: evergreen, edible
Eleagnus x ebbingei: evergreen, edible, incredibly drought resistant, nitrogen fixing.
I have both planted on my land here in Barcelona, but they are only 1 year old, so I cannot say about growth speed. However, I have seen an Eleagnus x ebbingei in the area. They get massive and very lush.
