Finely chop the onion and garlic. Dice the carrots and sweet potatoes.
Heat the olive oil in a large saucepan over medium heat. Add the onion and sauté for about 5 minutes, until softened.
Stir in the garlic and oregano, cooking for 1 minute until fragrant.
Add the carrots, sweet potatoes, and tomatoes. Stir well and cook for another minute.
Pour in the vegetable stock, bring to a boil, then reduce the heat and simmer for 20 minutes, or until the vegetables are tender.
Once cooked, remove from the heat and stir in the parsley. Blend the soup with a hand blender until smooth and creamy.
Add the chopped cabbage and drained lentils to the soup. Return to the heat and simmer for another 5 minutes, until the kale is wilted and the soup is hot.
Season to taste and serve warm with rice or wholesome bread.