Place the potatoes in a large pot and cover with salted water. Bring to a gentle boil and cook until they are just tender when pierced with a fork, about 15-20 minutes. Watch for the skin to loosen for easy peeling.
Drain the potatoes in a colander and let them cool slightly until they are comfortable to handle, about 5 minutes. While still warm, peel off the skins using your fingers or a small knife.
Chop the peeled potatoes into bite-sized cubes, placing them into a large mixing bowl. The warm flesh will absorb the dressing better, so work quickly.
In a separate small bowl, whisk together the mayonnaise, Dijon mustard, and apple cider vinegar until smooth and slightly bubbly. This creates a flavorful, tangy dressing.
Pour the dressing over the warm potatoes and gently fold with a spoon or spatula, ensuring each piece is coated evenly. The warmth helps the potatoes soak up the flavors.
Add the finely chopped celery and red onion to the bowl, folding them into the salad to add crunch and freshness. The aroma of vegetables should be bright and green.
Fold in the chopped hard-boiled eggs, distributing them evenly throughout the salad. The mixture should look creamy with colorful flecks of vegetables and eggs.
Season the potato salad with salt and freshly ground pepper to taste. Taste and adjust the seasoning to balance the tanginess and richness.
Cover the bowl with plastic wrap and refrigerate for at least 4 hours, or overnight. The flavors will meld and deepen, and the texture will firm up slightly.
Before serving, give the salad a gentle stir to redistribute the dressing. Serve chilled or at room temperature for a creamy, flavorful potato salad with a delightful crunch.
