Cut roast into 6-8 chunks.Add 32oz.carton of beef broth to pressure cooker,add meat.Put on high heat until it starts to jiggle,reduce to medium-low,cook for 40 minutes
Carefully remove pressure cooker and place under cold running water to relieve pressure.Remove meat with a slotted spoon to a platter,use 2 forks to shred meat and discard any fat.Pour remaining beef broth into a large pot.
While meat is cooking,peel & dice potatoes, put in cold water to keep from turning brown,also cut up the cabbage, dice the onion & celery.
Add the shredded meat back into beef broth,add tomato juice,fresh and frozen vegetables, and seasonings. Cover and simmer for 1 hour or longer,stirring a few times
Sometimes the leftover soup will may need some more beef broth added as the vegetables soak up the broth.
NOTE:Some people do not like using a pressure cooker,you can prepare the meat however you like as long as it is tender.