• Step 1: In a large pot, cover the peeled and cubed potatoes with cold water. Bring to a boil over high heat, then reduce heat and simmer for 10-15 minutes, until the potatoes are tender when pierced with a fork.
• Step 2: Drain the potatoes and let them cool slightly, then transfer to a large mixing bowl.
• Step 3: In a skillet, cook the diced bacon over medium heat until crispy, about 8-10 minutes. Transfer the bacon to the bowl with the potatoes, reserving 2 tablespoons of the bacon fat in the skillet.
• Step 4: Add the diced onion to the reserved bacon fat and sauté for 5-7 minutes, until softened and translucent.
• Step 5: In a small bowl, whisk together the apple cider vinegar, sugar, Dijon mustard, salt, and pepper.
• Step 6: Pour the vinegar dressing over the warm potatoes and bacon, then add the sautéed onions. Gently toss to combine, making sure the potatoes are evenly coated.
• Step 7: Stir in the chopped fresh parsley and adjust seasoning to taste.
• Step 8: Serve the German potato salad warm or at room temperature.