Wash and cut potatoes into ½-inch cubes (leave skin on for texture).
Boil in salted water for 12–15 minutes until tender but firm. Drain and set aside.
In a skillet, cook chopped bacon until crispy. Remove bacon, leaving 2 tbsp fat in the pan.
Add diced onion to the bacon fat and cook until translucent (3–4 minutes).
Whisk in vinegar, mustard, sugar, and broth. Simmer for 2 minutes. Season with salt and pepper.
Gently fold potatoes and bacon into the warm dressing. Sprinkle with parsley.
Best enjoyed immediately while warm.