Brown the ground beef in a large pot over medium heat. Break it up as it cooks until no pink remains.
Add the diced onion and minced garlic to the pot. Cook for 3 minutes until the onion softens.
Stir in the sliced carrots and celery. Cook for another 3 minutes to start softening the vegetables.
Add the cubed potatoes, chopped zucchini, and green beans. Pour in the diced tomatoes with their juices and the beef broth.
Sprinkle in the thyme, oregano, salt, and pepper. Stir everything together.
Bring the mixture to a boil, then reduce the heat to low. Cover and simmer for 25 minutes until the potatoes are tender.
Taste and adjust salt or pepper if needed before serving.