Dice 1 of the onions. Heat a large pot over medium-high heat and add 4 tablespoons of the olive oil. Add the onion and sauté until lightly browned, about 5 minutes. Drain and rinse the chickpeas, kidney beans, and fava beans, and add them to the onion along with 4 of the minced cloves of garlic, the turmeric, and lentils. Sauté for 1 minute, then add the stock and bring to a boil. Boil the beans, covered, for 1 hour. Tilt the lid so the pot is partially covered and simmer, stirring occasionally, for 1 1/2 hours. Season with salt. Slice the remaining 2 onions into thin half moons. Heat a sauté pan over high heat and add the remaining 3 tablespoons olive oil. Add the onions and fry, stirring frequently, until the onions are brown and caramelized. Add the remaining garlic and the mint and sauté for 1 minute. Season with salt and set aside.
Add the noodles to the soup and cook until tender, 6 to 8 minutes. When the noodles are almost done, add the leafy greens and the fresh herbs and cook for 2 minutes. Serve with a large dollop of yogurt and a few tablespoons of the sautéed onion mixture.
Per serving: 560.0 calories, 230.0 calories from fat, 25.0g total fat, 5.0g saturated fat, 45.0mg cholesterol, 950.0mg sodium, 56.0g total carbs, 5.0g dietary fiber, 15.0g sugars, 26.0g protein Nutritional analysis provided by TasteBook, using the USDA Nutrition Database