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. Transfer beef to a plate and set aside.
02 - In the same pot, add onion, garlic, carrots, and celery. Sauté for 5 minutes until vegetables begin to soften and onions turn translucent.
03 - Stir in red bell pepper, zucchini, and green beans. Continue cooking for 3 minutes to allow flavors to meld.
04 - Return seared beef to the pot. Add diced tomatoes with juice, tomato paste, beef broth, water, dried thyme, oregano, bay leaves, salt, and black pepper. Stir thoroughly to combine all ingredients.
05 - Bring mixture to a rolling boil, then reduce heat to low. Cover with lid and simmer for 30 minutes until beef becomes tender and vegetables are cooked through.
06 - Add orzo pasta to the pot and simmer uncovered for 10 minutes, stirring occasionally to prevent sticking, until pasta reaches al dente texture.
07 - Stir in fresh spinach leaves and cook for 2 minutes until wilted. Taste and adjust seasoning with additional salt and pepper as needed.
08 - Remove and discard bay leaves. Ladle hot soup into serving bowls and garnish generously with chopped fresh parsley.