Wash all vegetables well, including the kombu - do not peel. In a 12 quart or larger stockpot or soup pot, toss in carrots, onions, leek, celery, potatoes, sweet potatoes, yam, garlic, parsley, comb, peppercorns, allspice, sea salt, and bay leaves. Add water to the pot within about 1-2 inches from the top. Cover and bring to a boil.
Reduce to simmer, remove lid, and simmer for 2-4 hours, preferably 4 hours. As it simmers some of the water will evaporate, if the veggies start showing, add a bit more water. Simmer until you can taste the richness of the veggies in the broth.
Pour the broth through a strainer, make sure you have a pot or bowl beneath to catch all the broth. Cool completely, then store in quart size son jars or gallon sized freezer bags. Will keep in fridge 5-7 days or frozen up to 4 months.
If freezing in glass, COOL COMPLETELY! Fill only to shoulders of jar, leave lid off or loose and leave space between jars until frozen, or wrap a tea towel in between jars to cushion. If freezing in gallon sized baggie, fill and remove as much air as possible, freeze laying flat in freezer. Consume within about 4 months, thaw in refrigerator and use in soups, stews and anywhere else you would use a veggie broth, but mostly warm up a cup and enjoy!