In 5 litre saucepan, saute onion in oil until golden. Stir in carrots, chicken broth, tomatoes, chili sauce, brown sugar, vinegar, Worcestershire sauce, and mustard. Mash half of beans with fork; add mashed beans and whole beans to soup. Blend well. Bring to a boil. Cover. Reduce heat and simmer 30 minutes or until carrots are tender. Stir in SPAM and parsley. Simmer 2 minutes.