Pre-heat grill to high heat and brush both sides of eggplant with olive oil. Sprinkle with salt and pepper to taste then grill until tender, about 4-5 minutes per side, rotating twice on each side before flipping.
While eggplant is grilling, whisk together tahini sauce in a small bowl.
Remove eggplant from grill and place on a platter. Serve eggplant warm with tahini sauce drizzled on top. Garnish with fresh mint or parsley if you wish.