Heat a large stockpot over medium heat. Add bacon and cook until brown and crispy. Transfer to a paper towel-lined plate; set aside.
Wipe pot with paper towels to remove grease. Then melt better over medium heat. Whisk in flour until lightly browned -about 1 minute. Then add whisk in milk, and cook, stirring constantly until thickened. about 1-2 minutes. Stir in potatoes and green onions.
Bring to a boil; reduce heat and simmer until potatoes are tender, about 15-20 minutes. Stir in cheese, sour cream, salt and pepper to taste. Add more milk if soup consistency is too thick.
Serve immediately, garnish with green onion, cheese and bacon , if desired.
Recipe by The Gingham Apron at https://www.theginghamapron.com/baked-potato-soup/