1 1/2  quarts yellow split peas, dried
1 1/2  gallons {vegetable stock} or  gallons water
3  quarts potatoes (3 pounds)
1 1/2  quarts celery stalks, coarsely chopped
3 cups carrot, peeled and chopped
2  quarts onions, coarsely chopped
3 cups turnips, coarsely chopped
3 cups parsnips, coarsely choppled
2 tablespoons {dried mustard}, or more to taste
1 teaspoon allspice
1 tablespoon ground cumin
1 tablespoon marjoram
1 tablespoon thyme
2 tablespoons salt
 black pepper to taste

Rinse the split peas. Bring the peas and the stock or water to a boil.

At the boil, add the chopped vegetables, reduce the heat, and simmer for 45-60 minutes, or until the split peas are very soft and almost disintegrating. Use a heat diffuser to prevent scorching.

Purée the soup in a blender or food processor until it is quite smooth. It will be very thick.

Add the herbs, spices, and salt and pepper and reheat gently.