Preheat your oven to 425℉. Toss the quartered potatoes with 2 tablespoon olive oil, ½ teaspoon salt and ¼ teaspoon pepper. Roast for 35-40 minutes, tossing half way through.
To make the sauce, simply combine the Greek yogurt, tahini, lemon juice, remaining 2 tablespoon olive oil, fresh herbs, ½ teaspoon salt and ¼ teaspoon pepper. Set aside.
When the potatoes are done, toss with 3-4 tablespoon of the sauce (more or less based on your preference) and top with additional fresh herbs if desired.
Serve warm or at room temp.