Heat the olive oil in a Dutch oven or large pot over medium heat. Add the leeks, carrots and celery and cook for 5-6 minutes until softened. Add the garlic and cook for 30 seconds more.

Add the cabbage, tomatoes, vegetable stock and thyme to the pot and stir well. Bring to a boil, then the reduce the heat to medium low and simmer for 15 minutes or until the vegetables are tender.

Remove from heat and remove the thyme sprig. Stir in the lemon juice and season with salt and pepper to taste. Garnish with freshly chopped parsley or additional thyme leaves as desired. Enjoy!