In a large saucepan place the halved potatoes in salted cold water till potatoes are submerged. Add 1 teaspoon salt and 2 tablespoons of cider vinegar, and bring to a boil, then reduce heat and simmer for approximately 10-15 minutes, or till fork tender.
Drain the water away and allow the potatoes to cool.
Once cooled, cut the potatoes into bite size pieces, then transfer to a large mixing bowl.
Add the celery, onion, and gherkins.
Separately, in a small bowl make the dressing by combining the garlic, mustard, sugar, vinegar, pickle water, mayonnaise, sour cream, salt and pepper.
Carefully mix the potato salad to ensure an even coating in dressing, then garnish with sliced eggs and parsley .
Cover and chill in the refrigerator for at least 2 hours.
This dish is best made the day before for the flavours to fully come together.
Select the right kind of potato. Waxy potatoes work best as they are low in starch and high in moisture, so they retain their shape well after boiling. If the potatoes are too starchy (floury), they become mushy and fall apart.
The potatoes should be added to salted cold water rather than boiling, otherwise they will cook too quickly on the outside, while remaining raw inside.
The potatoes are boiled in plenty of salted water, with a splash of vinegar to prevent them from overcooking and becoming mushy.
After cooling, add the dressing and gently mix, ensuring the potatoes are evenly coated in dressing.
Garnish with sliced hard boiled eggs for extra creaminess and parsley.
Cover and chill for at least two hours, the longer it rests, the tastier it will be.
Potato salad will keep covered in the fridge for up to 4 days. It is not suitable for freezing.
Run out of gherkins? You can use pickled jalapeños and their pickling water.
Don't have sour cream? Increase the mayonnaise to ¾ cup and add 1 tablespoon lemon juice.
No red onions? Use a white onion sliced finely. In a small bowl mix together 1 tablespoon white wine vinegar, 1 teaspoon sugar and ½ cup cool water. Add the sliced onion ensuring it is completely submerged (if not, add a little more water) and set aside for 20 minutes. Drain the liquid away before using the onions.