01 - Place peeled and cubed potatoes in a large pot. Cover with cold water, add 1 tablespoon salt, and bring to a boil. Reduce heat and simmer for 10 to 12 minutes until potatoes are fork-tender. Drain and allow to cool slightly.
02 - While potatoes cook, fry chopped beef bacon in a large skillet over medium heat until crisp. Transfer bacon to a paper towel-lined plate to drain excess fat.
03 - In a large bowl, whisk together sour cream, mayonnaise, Dijon mustard, and black pepper until smooth.
04 - Add warm, drained potatoes to the bowl with the dressing. Gently fold potatoes into the mixture to evenly coat.
05 - Add celery, green onions, shredded cheddar cheese, parsley, and most of the cooked beef bacon. Gently mix until all ingredients are thoroughly combined.
06 - Adjust with additional salt and pepper to your preference.
07 - Transfer to a serving bowl or platter. Garnish with reserved green onions, crisp beef bacon, and extra parsley. Serve warm, at room temperature, or chilled.