Heat the oil in a large nonstick skillet over medium heat.
Add onion and garlic, and cook, stirring frequently, until onion is soft, about 5 minutes.
Add eggplant and water, and cook, stirring frequently, until eggplant is tender, about 5 minutes.
Add lamb and cook until no longer pink, about 3 minutes.
Stir in tomatoes, 1/2 cup of mint, 1/2 cup of dill, and salt, and bring to a boil.
Reduce to a simmer, cover, and cook 20 minutes, or until lamb is tender.
Meanwhile, cook orzo according to package directions. Drain.
Preheat oven to 350°F (180°C). Combine yogurt, flour and egg whites in small bowl.
Stir drained orzo into lamb mixture. Spoon mixture into an 28cm x 18cm baking dish.
Cover and bake 10 minutes.
Uncover dish and spoon yoghurt mixture over top.
Bake until pasta is piping hot, about 20 minutes.
Sprinkle remaining 1/4 cup mint and 1/4 cup dill on top and serve.