Wash the peas and soak them overnight in 5 quarts of water. Drain and reserve 1 quart of liquid.
Simmer the meat partly covered, in 10 quarts of water until tender. Remove the meat and shred it, after discarding the skin, bone and excess fat. Reserve meat stock.
Cook the peas and onions in the stock until both are soft. Press through a sieve.
Mix the flour with 1 quart of cold liquid from the peas, and add to the meat stock. Heat the mixture, stirring until somewhat thickened; then add the purée and shredded meat. Add salt if needed. Total measure cooked, about 13 quarts; 52 servings, each 1 cup.