Bake Potatoes. This can be done in advance. Scoop center out of potatoes. Simmer milk in large stock pot until bubbling, stirring often. Be careful not to scald. In a separate pan, melt butter. Add flour, mix well to create a roux. Add butter/flour mixture to milk. Wisk if necessary and bring up to a boil until it is as thick as you desire. Add dry chicken broth and pepper. Add potatoes to the soup. Serve in bowls topped with shreadded cheese. Put under broiler until cheese is melted. Top with a layer of bacon and sour cream.