Spray a large sauce pan with a bit of Pam. Melt butter, or add oil and cook onion for about 3 min. Add the ham and cook 3 more min.
Meanwhile cover potatoes in water and cook in the microwave for 5 min.; drain.
Add all the ingredients, along with the potatoes to the pan. Bring to a boil, then turn down to low and simmer for 30 minutes. You may want to thicken with flour or add milk to get the consistency you like.