Preheat your oven to 350°F. Pierce each potato several times with a fork. Rub potatoes with vegetable oil and sprinkle with kosher salt. Bake directly on the oven rack for 60 minutes until tender. Let cool, then cut into bite-sized pieces, keeping the skins on.

While potatoes bake, cook bacon in a large skillet until crispy. Reserve 2 tablespoons of bacon grease and chop the bacon into small pieces. Set aside for garnish.

In a large heavy-bottomed pot, melt butter and bacon grease over medium-low heat. Add diced onions and cook for 5-7 minutes until translucent and softened, not browned.

Slowly add flour to the butter and onion mixture, stirring constantly to prevent lumps. Cook for 2-3 minutes, stirring continuously to cook the flour and create a blonde roux.

Gradually add chicken stock, stirring constantly to prevent lumps. Add water, sugar, basil, celery salt, and black pepper. Increase heat to medium-high and bring to a boil while stirring frequently.

Once boiling, slowly add heavy cream, stirring constantly. Return to a gentle boil, then reduce heat to medium. Add the baked potato pieces and simmer for 10-15 minutes until heated through.

Taste and adjust seasoning as needed. Ladle into bowls and top with shredded cheese, crispy bacon, sour cream, and fresh chives.