In a large pot, heat vegetable oil over medium heat until it shimmers. Add the chopped onion, diced carrots, diced celery, and minced garlic, stirring frequently for about 5-7 minutes until the vegetables soften and the onion turns translucent.

Add ground beef to the pot, breaking it apart with a wooden spoon. Cook for 6-8 minutes, stirring occasionally, until browned and no longer pink.

Pour in beef broth, stirring to combine. Increase heat to high and bring to a gentle boil for 5-6 minutes.

Once boiling, add corn and chopped green beans. Sprinkle in dried thyme, dried parsley, salt, and black pepper. Stir well to distribute evenly.

Reduce heat to low, cover pot, and let soup simmer gently for 30-40 minutes.

Ladle warm soup into bowls and serve, ideally with crusty bread for dipping.