Mince garlic and slice scallions. Combine shrimp, olive oil, garlic, and scallions together and allow to marinate for about 20 minutes.
Rinse grape leaves and remove stems.
Season yogurt with harissa, salt and pepper. Grill for two minutes on each side. Remove shrimp from grill and place on a plate, pour harissa yogurt garnish over shrimp and serve. Preheat the grill for 15 minutes before cooking. 1 Clove garlic 3 oz.