Cut your baby potatoes into quarters—aim for pieces roughly the size of walnuts. Drop them into salted boiling water and cook for 12-15 minutes until they're fork-tender but still holding their shape. I always test one by piercing it deeply; if it slides off the fork, you're done. This timing matters because overcooked potatoes turn mushy and won't absorb the dressing the way we need them to.

While potatoes cook, whisk together mayo, Dijon mustard, sweet pickle relish, and apple cider vinegar in a large bowl. The acid from the vinegar cuts through the richness of the mayo, which is why I never skip it. Taste as you go—you want brightness, not just creamy.

Drain your hot potatoes immediately and transfer them to the dressing bowl while they're still steaming. This is the secret moment that changes everything: fold gently for 2-3 minutes while the warm potatoes actually absorb the dressing instead of sitting in it. I've watched the difference—warm potatoes that drink the dressing versus cold potatoes that just wear it.

Add your hard-boiled eggs, cooked chicken, shredded cheddar, and diced celery. Fold everything together gently—no aggressive stirring—because we want the chicken pieces and egg chunks to stay intact, not break down into a paste. This is when the salad goes from looking homemade to looking genuinely intentional.

Stir in the fresh dill and season with salt and black pepper. Do a final taste here because the potatoes will keep absorbing flavor as it sits, so season just slightly under what feels right. Let everything sit at room temperature for 10-15 minutes before serving so the flavors have time to actually know each other.