Begin by heating olive oil in a large pot over medium heat. Once shimmering, add chopped onion, diced carrots, and chopped celery stalks. Sauté for approximately 5 minutes, or until the onion becomes translucent.

Introduce seasonal vegetables to the pot. Stir and sauté for an additional 2-3 minutes, allowing the colors to brighten.

Pour in fire-roasted diced tomatoes and vegetable broth. Toss in bay leaves and red pepper flakes. Stir and bring to a gentle simmer.

Once simmering, reduce the heat and let cook uncovered for 25 minutes, stirring occasionally.

Fold in chopped greens into the simmering soup and cook for an additional 5 minutes until they wilt.

Remove from heat and stir in lemon juice. Adjust seasoning with salt and pepper as needed.