easy spicy cod fish stew with tofu

1 package of soon du bu seasoning (sold in tofu aisle refridgerated)
1 package of soft tofu or soon du bu (silken tofu in long tube)
1 frozen or fresh piece of cod (1/2 lb)
1 sliced leek (1, 2 inch leek sliced in half lengthwise)
1/2 cup of frozen or fresh shrimp (optional)
1/2 sliced onion
1 egg (optional)
salt as needed to taste

Boil 5 cups of water in a pot.  When boiling, add the soup mix and the tofu and seafood along with the leek and onions.  When boiling again, add the egg and stir.  Make sure seafood is cooked through and then serve with white rice.