Heat the olive oil in a large pot or Dutch oven and fry the red onion, carrot and celery for 5-6 minutes until they soften.
Stir in the garlic and rosemary and continue to cook for another minute until fragrant. Add the tomato paste and stir to combine.
Next, stir in the pearl barley and adzuki beans and then add the vegetable stock. Bring to a boil, then lower the heat and cook with a lid on for 25 minutes until the pearl barley is tender.
Stir in the lemon juice and kale and simmer for another 2-3 minutes until the kale wilts. Season to taste and serve on its own or with some crusty bread.
