01 - Heat olive oil in a large pot or Dutch oven over medium-high heat. Add beef stew meat and sear on all sides until browned, approximately 5 minutes. Remove beef from pot and set aside.
02 - In the same pot, add diced onion, minced garlic, sliced carrots, and sliced celery. Sauté for 5 minutes until vegetables begin to soften.
03 - Stir in red bell pepper, zucchini, and green beans. Cook for another 3 minutes to begin softening.
04 - Return beef to the pot. Add diced tomatoes with juice, tomato paste, beef broth, water, dried thyme, dried oregano, bay leaves, salt, and pepper. Stir well to combine. Bring to a boil, then reduce heat to low. Cover and simmer for 30 minutes until beef and vegetables are tender.
05 - Add orzo pasta to simmering soup. Continue cooking uncovered for 10 minutes, stirring occasionally, until orzo is al dente.
06 - Stir in fresh spinach leaves and cook until wilted, about 2 minutes. Adjust seasoning with salt and pepper as needed. Remove and discard bay leaves before serving.
07 - Ladle hot soup into bowls and garnish with chopped fresh parsley.