🥔 Austrian-Style Potato Salad (Erdäpfelsalat)

Note: I prefer the potato peels left on; the original recipe uses peeled potatoes and boils the skins with the potatoes for the starch

Ingredients

2 pounds (1kg) Yukon Gold potatoes, quartered, and cut into 1/2-inch-thick slices
Kosher salt
3 tablespoons (45ml) white wine vinegar, divided, plus more to taste
1/4 cup (60ml) extra-virgin olive oil
1 tablespoon (15ml) Dijon mustard
3/4 cup (90g) minced red onion, from about 1 small onion
2 tablespoons (6g) minced fresh chives
1/2 cup (120ml) homemade or store-bought low-sodium chicken stock
2 teaspoons (about 10g) sugar
Freshly ground white or black pepper
(optional) juice from 1/2 lemon

Place sliced potatoes in a large saucier or Dutch oven and cover with water. Season generously with salt. Bring to a boil over high heat and simmer until potatoes are tender, about 15 minutes.
Drain potatoes, and transfer to a rimmed baking sheet. Immediately sprinkle with 2 tablespoons (30ml) vinegar and set aside to cool. When they are cool enough to handle, transfer potatoes to a large bowl.
Add remaining vinegar, olive oil, mustard, red onion, chives, chicken stock, and sugar. Using a rubber spatula or wooden spoon, roughly stir and fold mixture so that potatoes release some starch and liquid begins to thicken a little. Season to taste with more salt and white or black pepper. Set aside to rest for at least 30 minutes and up to overnight. (If resting longer than 4 hours, cover bowl and transfer to refrigerator.) Stir again vigorously to thicken dressing; it should have a loose but not soupy consistency. If it's too thick, thin it out with a little extra water or chicken stock and re-season. Serve cold or at room temperature.