Begin by dicing the Russet or Golden potatoes into bite-sized cubes. In a large pot, add enough water to cover the potatoes and bring to a rolling boil. Cook the potatoes for about 15-20 minutes, or until fork-tender, then drain and set aside.

In a large saucepan, combine chicken stock, diced sweet yellow onion (if using), salt, and black pepper. Pour a splash of cold water and bring to a gentle simmer over medium heat for about 20 minutes.

Melt ¼ cup of butter in a separate saucepan over medium heat. Whisk in ¼ cup of all-purpose flour to create a roux, cooking for 2-3 minutes until it turns light golden.

Slowly whisk the roux into the simmering broth, blending well to avoid lumps. Gradually add in 1 cup of heavy whipping cream, stirring for another 5 minutes.

Gently fold the reserved, cooked potatoes into the creamy soup base and stir well. Let the soup simmer for an additional 5 minutes.

Ladle servings into bowls and top with cheddar cheese, crispy bacon bits, and green onions before serving hot.