Either place the pickling spice in cheesecloth and steep in the chicken broth or simmer the spice directly in the broth for 5+ minutes.  Strain. 

Saute the onion in any mild oil until tender. 

Add the broth and the potatoes, simmer until not quite tender. 

Add the carrots and cabbage, cook until almost tender. 

Submerge the fish in the picking liquid, cover and cook until done-5-7 minutes depending on thickness of the fish.