Clean and Chop the Potatoes: Rinse the potatoes under cool running water, scrubbing with your hands or a vegetable brush to remove any dirt. Pat dry, then chop into bite-sized pieces, about eight pieces per potato.
Cook the Potatoes: Place the potato pieces in a 2-quart pot and cover them with water. Bring to a boil, then reduce the heat to medium-high. Simmer for 10-12 minutes, or until a fork easily pierces them.
Drain: Drain the potatoes and transfer them to a plate or bowl. Cover to keep warm.
Cook the Bacon: Wipe out the pot, then cut the bacon into 1-inch pieces and cook over medium heat until crispy. Remove with a slotted spoon and place on a paper towel-lined plate.
Sauté the Onions: In the same pot with the bacon drippings, cook the chopped onions for about 1 minute, stirring frequently.
Make the Dressing: Remove the pot from heat and stir in the vinegar, water, mustard, sugar, salt, and pepper. Return to the stove and heat until it simmers, stirring for another minute.
Combine Everything: Remove from heat and gently mix in the potatoes, letting them absorb most of the liquid. Stir in the crispy bacon and parsley.
Serve: Transfer to a bowl and enjoy warm.
Notes
Start with Cold Water: Place the potatoes in cold water before boiling to ensure even cooking.
Crisp the Bacon: Cook the bacon until crispy—it adds texture and provides the fat needed for the vinaigrette.
Adjust the Sweetness: Add more or less sugar based on your taste.
Let It Rest: Allow the salad to sit for a few minutes before serving so the flavors can meld.