Heat 2 tablespoons of olive oil in a large Dutch oven over medium heat. Once the oil shimmers, add the chopped onion, diced celery, and sliced carrots. Cook these fragrant vegetables for about 5 minutes, stirring occasionally, until they soften and the onion turns translucent. Stir in the minced garlic and sauté for an additional 30 seconds until fragrant.

Add ¾ cup of pearl barley along with 1 teaspoon of Italian seasoning, 1 teaspoon of dried thyme, ½ teaspoon of salt, and ½ teaspoon of black pepper to the pot. Stir well to combine everything.

Pour in 6 cups of low-sodium vegetable broth and add a 15 oz can of petite diced tomatoes along with one bay leaf. Stir everything together until well combined, then increase the heat slightly to bring the mixture to a gentle simmer.

Cover the pot with a lid, reduce the heat to low, and let it simmer for 25 minutes. Keep an eye on it, giving a gentle stir if needed.

Once the 25 minutes are up, add in ½ pound of chopped Yukon Gold potatoes. Stir the soup and cover again, letting it simmer for an additional 20 to 35 minutes until both the barley and potatoes are tender.

In the last 5 minutes of cooking, stir in ¾ cup of frozen green beans, ensuring they’re evenly distributed throughout the soup.