Finely mince onion, celery & carrot. Cut potatoes into bite sized pieces.

Combine potatoes, celery, onion, carrot, chicken broth, salt & vinegar in saucepan. Simmer 20 minutes.

Mix flour into milk, then add to veggies & simmer 5 to 8 minutes.

Add shredded cheeses & simmer until melted and soup thickens.

Top serving with crumbled cooked bacon and chopped green onion.