Insert whole cloves in onion. Combine onion, roast, water, salt, pepper, and bay leaf in a large Dutch oven; bring to a boil. Reduce heat; cover and simmer 1 1/2 hours.
Remove roast from stew; cool slightly. Remove meat from bone, discarding bone. Chop meat into bite-size pieces, and return to stew; cool to room temperature. Refrigerate stew until all fat has risen to the top; skim off and discard fat. Remove whole onion from stew; remove and discard cloves. Chop onion, and return to stew.
Add remaining ingredients to stew, stirring until well blended; bring to a boil. Reduce heat; cover and simmer 45 minutes. Uncover and cook an additional 30 minutes. Remove and discard bay leaf.
Serve stew immediately in individual serving bowls.