01 - Heat olive oil in a large pot or Dutch oven over medium-high heat. Add beef pieces and sear on all sides until well browned, approximately 5 minutes. Remove beef from pot and set aside.
02 - In the same pot, add onion, garlic, carrots, and celery. Sauté for 5 minutes until vegetables begin to soften and onion becomes translucent.
03 - Stir in red bell pepper, zucchini, and green beans. Continue cooking for another 3 minutes to slightly soften vegetables.
04 - Return browned beef to the pot. Add diced tomatoes with juice, tomato paste, beef broth, water, dried thyme, dried oregano, bay leaves, salt, and pepper. Stir thoroughly to combine all ingredients.
05 - Bring mixture to a boil, then reduce heat to low. Cover pot and simmer for 30 minutes, or until beef becomes tender and vegetables are cooked through.
06 - Add orzo pasta to simmering soup. Cook uncovered for 10 minutes, stirring occasionally to prevent sticking, until orzo reaches al dente texture.
07 - Stir in fresh spinach leaves and cook for approximately 2 minutes until just wilted. Taste and adjust seasoning with additional salt and pepper if needed.
08 - Remove and discard bay leaves. Ladle hot soup into serving bowls and garnish generously with chopped fresh parsley.