Wash and halve your potatoes and add to a large pot. Cover with cold water by a few centimetres.
Place over high heat on the stove with a lid on and bring to a boil. Once boiling, add a generous amount of salt and lower heat to medium for a relaxed boil.
Cook for 15-20 minutes, depending on the size of your potatoes. Keep an eye on these because the cooking time will vary.
Meanwhile, in a small frying pan over medium heat, heat olive oil and add the diced shallots, stirring frequently until caramelised and starting to crisp, about 8-10 minutes.
Drain your cooked potatoes and run under cold water to cool faster. Set aside.
Prepare dressing by combining sour cream, mayonnaise, mustards, hot sauce, diced pickled onions, pickled-onion liquid, chopped herbs, cooked shallots and any of their remaining oil, and pepper.
In a large bowl, add your boiled potatoes and your dressing and toss to evenly coat.
