In a soup kettle, cook the diced bacon. Sauté the onion in the bacon and drippings until translucent, about five minutes.
Add the chicken stock and simmer.
While the mixture simmers, scoop out the potatoes, which should still be warm. Chop any large chunks into about one-inch pieces.
Add the potatoes to the stock, then the salt and peppers.
In a saucepan, melt the butter over medium heat; add the flour and whisk to a smooth consistency. Reduce heat to low; cook for five minutes, stirring frequently.
To the kettle mixture, add the heavy cream and the Cheddar cheese. Bring to a boil, then reduce heat and stir constantly until the mixture thickens. Slowly add the butter-flour mixture, then fold in the sour cream.
Pour into serving bowls; sprinkle chives and parsley on top.Makes 6 quarts Source: