Make the meatballs: In a bowl, combine all meatball ingredients. Mix gently until just combined. Roll into small, marble-sized meatballs. Set aside.
Cook the onion base: Heat butter in a large pot over medium-low heat. Add sliced onions with a pinch of salt and cook 10–15 minutes, until very soft and beginning to turn golden. Add garlic, tomato paste, paprika, and turmeric. Cook 1–2 minutes until fragrant.
Blend: Add 2 cups of the bone broth to the pot. Blend until completely smooth using an immersion blender (or carefully transfer to a blender).
Simmer: Returnthe pot to the stove and add remaining broth. Bring to a gentle simmer. Add rice, carrots, and chickpeas. Simmer 15 minutes until the carrots are soft.
Add meatballs: Gently drop meatballs into the soup. Simmer uncovered 10–12 minutes, until the meatballs are cooked through and the rice is tender. Season with salt to taste.
Finish: Pour the soup into bowls. Add a squeeze of lemon juice and a garnish of chopped cilantro.