"This is my Rosetta stone of soup, a broth that can be transformed to meet myriad nutritional needs, serving as everything from a delicious sipping tea to the powerful base for more hearty soups and stews," says Rebecca Katz, whose Cancer-Fighting Kitchen workshop in September 2011 featured her recipes in the Bastyr Dining Commons, including Carrot-Ginger Soup with Magic Mineral Broth as its base. "So no matter what a person's appetite, it can provide a tremendous nutritional boost. This rejuvenating liquid, chock-full of magnesium, potassium, and sodium, allows the body to refresh and restore itself. I think of it as a tonic, designed to keep you in tip-top shape."
Rinse all of the vegetables well, including the kombu. In a 12-quart or larger stockpot, combine the carrots, onions, leek, celery, potatoes, sweet potatoes, yam, garlic, parsley, kombu, peppercorns, allspice berries and bay leaves. Fill the pot with the water to 2 inches below the rim, cover, and bring to a boil.
Remove the lid, decrease the heat to low, and simmer, uncovered, for at least 2 hours. As the broth simmers, some of the water will evaporate; add more if the vegetables begin to peek out. Simmer until the full richness of the vegetables can be tasted.
Strain the broth through a large, coarse-mesh sieve (remember to use a heat-resistant container underneath), then add salt to taste.
Let cool to room temperature before refrigerating or freezing.