Sauté the vegetables:
In a large pot, heat the olive oil over medium heat. Add the diced onion, carrots, and celery with a pinch of salt and pepper. Cook for 5-7 minutes, stirring occasionally, until softened. Add the minced garlic and cook for another minute until fragrant.
Season: Add the oregano, basil, thyme and chili flakes and cook for 1-2 minutes stirring frequently. If the pan is starting to dry out, add a splash of vegetable broth.
Add tomatoes and broth:
Stir in the diced tomatoes, vegetable broth, and water. Bring the mixture to a boil then let simmer for 2-3 minutes.
Cook the orzo:
Keeping it at a simmer, stir in the orzo pasta and chickpeas. Cook for 8-10 minutes, stirring occasionally, until the orzo is al dente.
Add spinach: Stir in the spinach until wilted and mixed in.
Adjust seasoning and serve:
Taste the soup and adjust seasoning if necessary. Ladle the soup into bowls and garnish with fresh parsley, if desired.