Step 1

Place 2 pounds quartered small Yukon gold potatoes and 1 tablespoon of the kosher salt in a large saucepan. Add enough cool water to cover by 1 inch, then bring to a boil over high heat. Reduce the heat to medium and simmer until the potatoes are cooked through and easily pierced with a knife, 8 to 13 minutes.

Step 2

Meanwhile, grate 1/2 medium English cucumber on the large holes of a box grater onto several layers of paper towel or a clean dish towel. Gather up the sides of the towel together and squeeze out as much liquid from the cucumber as you can.

Step 3

Transfer the cucumber to a large bowl. Stir in 3/4 cup Greek yogurt, 2 thinly sliced medium scallions, 2 tablespoons finely chopped fresh dill, 1 tablespoon lemon juice, 1 tablespoon olive oil, 2 finely grated garlic cloves, the remaining 1 teaspoon kosher salt, and 1/4 teaspoon black pepper.

Step 4

When the potatoes are ready, drain in a colander. Let cool for 10 minutes so the potatoes are cool enough to handle but still warm.

Step 5

Gently stir the potatoes into the tzatziki. Cover and refrigerate for at least 3 hours or up to 1 day for the flavors to meld. Stir again, then taste and season with more kosher salt and black pepper as needed. Garnish with more chopped fresh dill.