Place peppercorns, bay leaf, oregano, ginger and parsley in cheesecloth.
Place the zucchini, red pepper, onion, mushrooms, celery, salt, peppercorn and bay leaf pouch, and water in a saucepan. Bring to a boil, then reduce heat to low medium and let it simmer, skimming off the foam.
Let it cook for 45 minutes to 1 hour.
In the last 5 minutes of cooking, add chopped tomato. When cooking is done, remove bay leaf and peppercorn pouch.