For marinade, whisk oregano, Greek seasoning, salt, pepper, yogurt, oil and lemon juice in a large bowl. Place lamb in a large shallow dish or heavy-duty resealable plastic bag. Pour marinade over lamb. Cover or seal; refrigerate 2 hours, turning occasionally.
Preheat oven to 425°F. Remove lamb from marinade; discard marinade. Place lamb on rack in roasting pan.
Roast lamb 25 minutes; reduce heat to 350°F (do not remove lamb from oven) and roast 1 hour, 15 minutes or until instant-read thermometer registers 145°F for medium-rare. Remove lamb from oven and let stand 15 minutes before slicing.
|Serving Size 1|
|Amount Per Serving|
|Calories 529||Calories from Fat 264|
|% Daily Value*|
|Total Fat 29g||44%|
|Saturated Fat 11g||53%|
|Total Carbohydrate 4g||1%|
|Dietary Fiber 0.22g||1%|