In a large mixing bowl, combine the ground chicken, panko breadcrumbs, egg, 2 tablespoons fresh dill, fresh parsley, garlic powder, onion powder, 1/2 teaspoon salt, 1/4 teaspoon black pepper, and lemon zest. Mix gently until just combined, being careful not to overmix.

Roll the mixture into approximately 1-inch diameter meatballs. You should get about 25-30 meatballs. Place them on a plate or baking sheet.

For best results, lightly pre-cook the meatballs: bake at 400°F (200°C) for 8-10 minutes, or air fry at 375°F (190°C) for 6-8 minutes, until lightly browned but not fully cooked through. This helps them hold their shape in the soup. Alternatively, you can drop them raw directly into the simmering broth (see step 4).

Heat olive oil in a large Dutch oven or heavy-bottomed pot over medium heat. Add the diced onion, carrots, and celery. Sauté for 5-7 minutes, or until the vegetables begin to soften.

Add the minced garlic and cook for another minute until fragrant.

Pour in the chicken broth and undrained diced tomatoes. Bring the mixture to a gentle simmer. If adding raw meatballs, carefully drop them into the simmering broth now.

Add the pre-cooked meatballs (if using) and orzo pasta to the simmering broth. Cook for 10-12 minutes, or until the orzo is tender and the meatballs are fully cooked through.

Stir in the fresh spinach and cook for 2-3 minutes, until wilted. Remove the pot from the heat.

Stir in the fresh lemon juice and the remaining 2 tablespoons of chopped fresh dill. Taste and adjust seasoning with salt and pepper as needed.

Ladle the hot soup into bowls and serve immediately. Garnish with extra fresh dill if desired.