1. In a large bowl, whisk together olive oil, lemon juice, cumin, salt and pepper. Stir in cilantro, garlic and oregano. Stir in lamb. Cover with plastic wrap and refrigerate 1 hour.Yogurt Sauce
2. In a bowl, stir together yogurt, mayonnaise, lemon juice, sugar and 1 tbsp water until smooth. Stir in parsley. Cover and refrigerate until serving.Rice
3. Meanwhile, in a medium lidded pot, heat oil over medium heat. Stir in cumin, turmeric and rice; cook 1 minute. Pour in chicken broth and salt. Cover and bring to a boil. Reduce heat to a simmer and cook about 15 minutes, until liquid is absorbed. Let stand 5 minutes, covered, then fluff with a fork.
4. Heat a large saute pan over medium-high heat. Drain lamb and pat dry, reserving marinade. Add to skillet and cook 2 to 3 minutes, stirring once in a while, until pieces are seared but medium-rare. Pour in marinade; bring to a boil. Simmer 2 minutes. Serve lamb, using a slotted spoon, over rice with yogurt sauce, tomato, lettuce and harissa.