Green Mountain Potato Chowder

• 3 tomatoes (diced)
• 3 branches parsley left (whole)
• 2 carrots (peeled)
• 1 bay leaf
• 1/2 celery root
• 1/4 slab bacon
• 1,900 ml beef broth
• 290 gr maine potatoes
• 60 ml sour cream
• 4 slices pumpernickel