Creamy Japanese Potato Salad
Ingredients
1 large egg
1 pound Yukon Gold potatoes, peeled and cut into 2-inch chunks
1 tablespoon rice vinegar
½ teaspoon white granulated sugar
½ teaspoon plus ⅛ teaspoon salt, divided
¼ teaspoon ground black pepper
1 Japanese cucumber, or ½ of a regular English cucumber
2 ounces sliced deli ham, cut into bite-sized strips
⅓ cup Japanese-style mayonnaise (Kewpie® is the recommended brand)
¼ cup finely shredded carrot
2 green onions, chopped
1 teaspoon Dijon mustard
Directions
Place the whole egg in a small saucepan and cover it fully with 1 inch of cold water. Bring the water to a full rolling boil over high heat. Once boiling, cover the pan, remove it from heat, and let the egg sit undisturbed for 15 minutes. Drain the hot water, then transfer the egg to a bowl of ice water to cool for roughly 5 minutes, until it is cool enough to handle. Peel the shell and coarsely chop the egg, then set it aside.
While the egg cools, cook your potatoes: add the cut potato chunks to a medium saucepan, cover with enough salted boiling water to fully submerge them, and cook over medium heat for 15 to 20 minutes, until fork-tender. Drain all excess water, then return the potatoes to the warm pan.
Sprinkle the hot potatoes with rice vinegar, sugar, ½ teaspoon of salt, and black pepper. Mash the potatoes coarsely, leaving plenty of large, firm chunks intact (potatoes will break down further when you mix the full salad, so do not over-mash). Transfer the potatoes to a large mixing bowl, and spread them in an even layer up the sides of the bowl to speed up cooling. Let the potatoes cool completely for roughly 30 minutes.
While the potatoes cool, slice the cucumber thinly with a mandoline for even cuts, which will give you 1 ¼ to 1 ½ cups of sliced cucumber.
Put the sliced cucumber in a colander set in the sink, sprinkle with the remaining ⅛ teaspoon of salt, and toss to coat all slices evenly.
Let the salted cucumber rest for 10 minutes to draw out excess moisture. Then transfer the slices to a clean kitchen towel or stack of paper towels, and squeeze firmly to remove all extra water (this step keeps your finished salad from turning soggy).
Once the potatoes are fully cooled, add the chopped egg, prepared cucumber, ham, mayonnaise, shredded carrot, green onions, and Dijon mustard to the bowl. Gently fold all ingredients together until evenly combined. Cover the bowl and refrigerate for 30 minutes to let flavors meld before serving.
