In a small heavy skillet toast coriander, cumin, and crushed red pepper over medium heat about 5 minutes or until fragrant, shaking the skillet occasionally. Let cool completely. Transfer to a spice grinder and grind finely.
Meanwhile, heat the ¼ cup olive oil on a 5-qt. heavy pot.Add leek, celery, carrots, and salt. Cook over medium heat, stirring occasionally, about 5 minutes or until softened. Add garlic, ginger, and paprika. Cook and stir 1 minute. Add bell pepper, eggplant (if using), and a splash of water. Cook, covered, about 5 minutes or until just eggplant and bell pepper is just softened and carrots are almost tender. Add tomato paste and half of the ground spices; cook and stir 1 minute.
tir in broth, water, chickpeas, lentils, cilantro, parsley, and bay leaf. Bring to boiling. Reduce heat and simmer, covered, 15 to 20 minutes or until lentils are almost tender. Stir in tomatoes, greens, and orzo. Bring to boiling (add more water as needed to keep a soupy consistency). Remove from heat. Stir in lemon juice, the 2 Tbsp. olive oil, and remaining spices. Cover and let stand 20 to 30 minutes or until orzo is tender. Season to taste with salt and black pepper. Serve with desired toppers.