French Onion Dip Potato Salad

Name: French Onion Dip Potato Salad
Ingredients: Kosher salt; 2 pounds medium Yukon gold potatoes; 1/2 medium English cucumber; 2 medium stalks celery; 1 cup sour cream; 1/2 cup mayonnaise; 1 (1-ounce) packet onion recipe soup and dip mix, such as Lipton Recipe Secrets; 1/2 teaspoon freshly ground black pepper; 3 hard-boiled large eggs (optional); 1/2 medium bunch chives