Fill a large pot with water and add a generous amount of salt. Bring it to a rolling boil. Carefully add the halved baby potatoes and cook for 15 to 20 minutes, or until fork-tender. Drain and cool for about 10 minutes.
In a small mixing bowl, combine the olive oil, lemon juice, lemon zest, chopped dill, garlic powder, and a pinch of salt and pepper. Whisk until well combined. If desired, fold in Greek yogurt for a creamier dressing.
In a large mixing bowl, add the cooled potatoes and diced red onion. Pour the dressing over and gently toss until the potatoes are coated and the onion is distributed.
Cover the bowl and refrigerate for at least 30 minutes to allow flavors to deepen. Serve chilled or at room temperature.
Notes
For an appealing presentation, serve in a large bowl and garnish with fresh dill and lemon wedges.