Peel and dice the potatoes into uniform cubes. Place them in a large pot, cover with water, and boil until tender, about 15–20 minutes. Drain and set aside.

In a large pot, combine chicken stock, diced onion, salt, and black pepper. Simmer over medium heat for about 20 minutes.

In a separate saucepan, melt butter over medium heat. Whisk in flour to create a roux and cook for 2 minutes, stirring continuously until golden.

Slowly whisk the roux into the chicken stock mixture, stirring to prevent lumps. Cook for another 5 minutes to thicken.

Stir in heavy whipping cream and simmer on low heat for 20 minutes, stirring occasionally.

Gently stir in the cooked potatoes and simmer for an additional 5 minutes.

Ladle soup into bowls and top with bacon, cheddar cheese, and green onions. Serve hot.