Place four peeled and cubed potatoes in a pot with 1 cup each chopped celery with leaves and chopped onion. Add enough water to barely cover, bring to a boil, lower heat, cover and simmer 25 minutes. Crush potatoes with a spoon, thin with milk, and season to taste.
Cook 6 diced bacon strips in a saucepan, drain, add 3 cups cubed peeled potatoes, one 14 1/2-ounce can chicken broth, a grated carrot, 1/2 cup chopped onion, 1 tablespoon dried parsley flakes and 1/2 teaspoon each celery seed, salt and pepper. Cover and simmer 15 minutes. Combine 3 tablespoons each of flour and milk, add it to the soup and bring to a boil, cooking and stirring for two minutes. Add 8 ounces of cubed processed cheese and stir until cheese melts and soup is heated through.
For a twist, pierce four red potatoes with a fork and microwave on high for 13 minutes, cut in half and cool slightly. Heat 2 teaspoons olive oil in saucepan over medium-high heat, add 1/2 cup chopped onion and sauté 3 minutes. Add 1 1/4 cups fat-free chicken broth and stir in 3 tablespoons flour mixed with 1/2 cup milk. Add an additional 1 1/2 cups milk and stir constantly while cooking for one minute. Remove from heat and stir in 1/4 cup reduced fat sour cream, 1/2 teaspoon salt and 1/4 teaspoon black pepper. Discard skins and coarsely mash potatoes into soup. Serve topped with crumbled microwaved bacon, shredded cheddar cheese and sliced green onions.