01 - Heat olive oil in a large pot or Dutch oven over medium-high heat. Add beef pieces and sear on all sides until 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 release their aromas.
03 - Stir in red bell pepper, zucchini, and green beans. Continue cooking for another 3 minutes to begin softening the vegetables.
04 - Return browned beef to the pot. Add diced tomatoes with juice, tomato paste, beef broth, water, thyme, oregano, bay leaves, salt, and pepper. Stir thoroughly to combine all ingredients and dissolve tomato paste.
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 and cook uncovered for 10 minutes, stirring occasionally to prevent sticking, until orzo reaches al dente texture.
07 - Stir fresh spinach into soup and cook for 2 minutes until just wilted. Taste and adjust seasoning with additional salt and pepper if needed. Remove and discard bay leaves before serving.
08 - Ladle hot soup into serving bowls and garnish with chopped fresh parsley.