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, about 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 slightly soften the vegetables.
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 all ingredients.
05 - Bring mixture to a boil, then reduce heat to low. Cover and simmer for 30 minutes, until beef and vegetables are tender.
06 - Add orzo pasta to the simmering soup. Cook uncovered for 10 minutes, stirring occasionally to prevent sticking, until orzo is al dente.
07 - 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.
08 - Ladle hot soup into bowls and garnish with chopped fresh parsley. Serve immediately while hot.