Preheat oven to 350 degrees.
Cook pork tenderloin in 1 1/2 quarts water until tender.
Remove from broth and place in baking dish or roasting pan.
Reserve 2 cups of the broth.
Roll tenderloin in mixture of brown sugar, pepper, salt and flour.
Add tomatoes, onion, potatoes, 2 cups broth, and ketchup.
Bake for one hour at 350 degrees, or until mixture thickens slightly.
Remove from oven and allow to cool for 3 minutes before slicing.