Heat water and peas to boiling in Dutch oven; boil 2 minutes. Remove from heat; cover and let stand 1 hour. Add salt pork, onions, marjoram and pepper. Heat to boiling; reduce heat. Cover and simmer 1 hour. Skim fat if necessary.

Add carrots and celery. Heat to boiling; reduce heat. Cover and simmer until vegetables are tender, about 45 minutes. Remove salt pork; cut into 1/4-inch slices. Add pork to soup or serve separately with mustard if desired. Servings: 8 servings (about 1-1/2 cups each)