In a medium-size saucepan, combine potatoes and sea salt. Cover with water by one inch (two centimeters).

Bring to a boil over high heat. Reduce heat to medium-low and cook until potatoes are easily pierced by a fork. Drain the water and remove the potatoes from the pan.

Place in the refrigerator to cool for at least 15–20 minutes.

Once the potatoes have cooled, peel and cut into chunks.

Add parsley, onion, lemon juice, and mustard. Toss to coat.

Add mayonnaise and diced eggs. Adjust seasoning to taste.