Heat a large pot over medium-high heat. Add oil and ground beef. Break up and cook until browned, 6–8 minutes. Drain excess fat if desired.
Add onion, carrots, and celery to the pot. Cook until softened, about 5 minutes. Add garlic and cook 30 seconds until fragrant.
Stir in tomato paste, diced tomatoes, thyme, oregano, bay leaf, and a pinch of salt and pepper. Cook 1 minute.
Pour in beef broth, bring to a boil, then reduce to a simmer. Cook 15 minutes to let flavors meld. If using pasta, add it about 10 minutes before the end of cooking.
Stir in corn and green beans and simmer 5 more minutes until heated through. Remove bay leaf.
Ladle into bowls and garnish with chopped parsley. Adjust seasoning with salt and pepper to taste.
Notes
For a thicker soup, mash a cup of cooked vegetables and stir back into the pot.
Frozen vegetables work great and save prep time.
This soup freezes well—portion before freezing for easy meals.