In a large pot, add the olive oil over medium heat. Once hot, add the chopped onion, sliced carrots, and sliced celery. Sauté for about 5 minutes until the vegetables start to soften.

Stir in the minced garlic and diced zucchini, cooking for an additional 2-3 minutes until fragrant.

Add the vegetable broth and canned diced tomatoes to the pot.

Sprinkle in the Italian seasoning, salt, and pepper. Bring the soup to a boil, then reduce the heat to a simmer.

Let the soup simmer uncovered for about 30 minutes, stirring occasionally.

Before serving, taste the soup and adjust the seasoning if necessary.

Ladle the soup into bowls and garnish with fresh herbs if desired.