In a large pot brown the bacon, onion, and celery until onion is soft and translucent (about 5-7 minutes). Add garlic and stir for 30 seconds.
Stir in flour and cook for 1 minute to remove the raw flour taste. Stir in chicken broth and milk until well combined. Add potatoes and season with salt and pepper. Cover and simmer on medium-low to low for 10-15 minutes or until potatoes are tender. The smaller your potatoes the quicker they will cook.
When potatoes are tender remove from heat and stir in sour cream.
What to serve with Creamy Potato Soup