Rinse potatoes and place them in a pot. Fill the pot with cold water, making sure potatoes are covered.
Cook potatoes in salted, simmering water (over medium heat) until just done but not falling apart and cool completely before cutting.
Potato Salad:
Cut potatoes into 1/2 inch cubes and add to a large mixing bowl.
Add Parmesan cheese, green onion, lemon zest, dill, salt, and pepper and gently stir until all evenly mixed.
In a separate bowl, combine mayo, Dijon mustard, and sour cream until smooth and even.
Add mayo mixture to the potato mixture and gently mix until mayo mixture is evenly incorporated throughout the salad.
Refrigerate until ready to serve.
Video
Notes
String: Store potato salad in an airtight food storage container in the refrigerator for 3-4 days. Make sure to keep the container airtight either with the lid or plastic wrap.
Make Ahead: You can make the whole potato salad ahead of time and store it in the refrigerator in an airtight container. Potatoes can also be cooked the day before that way you can easily put the salad together in ten minutes when ready.