Pour broth into a large stockpot and bring to a boil over medium.

Peel potatoes and chop into 1/2 inch cubes; add to boiling stock. Return to boil and then simmer for 7-8 minutes or until potatoes are just tender. (Avoid overcooking so potatoes won't break apart.)

Add kale and mushrooms and continue to simmer for 5 minutes.

Slice chicken and toss into stock. Season with pepper.  Simmer until chicken has cooked through, and is no longer pink.

Serve soup with raspberries on the side.