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 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.
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. Continue cooking uncovered for 10 minutes, stirring occasionally to prevent sticking, until orzo reaches al dente texture.
07 - Stir in fresh spinach leaves and cook until wilted, about 2 minutes. Taste and adjust seasoning with additional salt and pepper if needed. Remove bay leaves before serving.
08 - Ladle hot soup into individual bowls. Garnish generously with chopped fresh parsley. Serve immediately while hot.