Place the kale, the finely chopped garlic clove, lemon juice, 2 tbsp of the oil and 1 tbsp of water in a blender and whizz to a paste. Add some freshly ground black pepper and transfer to a bowl.
Heat 1 tbsp of oil in a large wok or non-stick frying pan over a medium heat. Add the crushed garlic and the white and red cabbage and stir-fry over a high heat for 6-7 mins until the cabbage is just tender.
Serve on two warmed plates, topped with the kale pesto and walnut pieces.