This was really good! I made a couple of changes, though.
1. I doubled the amount of celery ( I had a lot I need to use)
2. I used celery leaves instead of parsely
3. I had some fresh fava beans, so I used them instead of the garbanzos
4. I used 1/2 an onion instead of a whole one
5. Used a few less olives (about 1 C)
So I guess my version was a bit different, but it is really tasty.