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Potato salad is an easy dish to make and transport to a summer potluck. But all too often the star of the show is mayonnaise, rather than the recipe’s namesake ingredient. We found that the secret to a creamy and light potato salad is to emulate the Austrians: Ditch the mayo and look to the soup pot.
We boil the spuds in a shallow pan with chicken stock, water, sugar, and salt, which leads to deeply flavored potatoes. We also found that adding a surprising ingredient, white vinegar, expanded the window of time during which the spuds go from properly cooked to mushy and broken.
This is because potato cells are held together by pectin, a large molecule that acts as a glue. This glue weakens when heated in water, allowing the cells to come apart, which first softens the potato and then breaks it apart. Vinegar’s acidity slows the breakdown of pectin, expanding the amount of time between the point when a potato starts to soften and when it fully breaks down.
We use Yukon Golds in this dish, as they have just enough starch to contribute creaminess without breaking apart. To finish our potato salad recipe, we add mashed potatoes to the dressing, which thickened it perfectly every time.
The finished salad should be creamy and loose, with chunks of potato that keep their shape but are very tender. If you can’t find cornichons, chopped kosher dill pickles can be used in their place. To maintain its consistency, don’t refrigerate the salad; it should be served within 4 hours of preparation.
2 pounds Yukon Gold potatoes (about 4 large), peeled, quartered lengthwise, and cut into 1/2-inch-thick slices
1. Bring potatoes, broth, water, 1 teaspoon salt, sugar, and 1 tablespoon vinegar to boil in 12-inch heavy-bottomed skillet over high heat. Reduce heat to medium-low, cover, and cook until potatoes offer no resistance when pierced with paring knife, 15 to 17 minutes. Remove cover, increase heat to high (so cooking liquid will reduce), and cook 2 minutes.
2. Drain potatoes in colander set over large bowl, reserving cooking liquid. Set drained potatoes aside. Pour off and discard all but 1/2 cup cooking liquid (if 1/2 cup liquid does not remain, add water to make 1/2 cup). Whisk remaining tablespoon vinegar, mustard, and oil into cooking liquid.
3. Add 1/2 cup cooked potatoes to bowl with cooking liquid mixture and mash with potato masher or fork until thick sauce forms (mixture will be slightly chunky). Add remaining potatoes, onion, cornichons, and chives, folding gently with rubber spatula to combine. Season to taste with salt and black pepper. Serve warm or at room temperature.