Heat 2 tsp of oil in a large lidded pan and gently cook 1/2 the spring onions, ginger and garlic for 5-10 minutes or until soft. Add 1 tbsp of miso, all the sweet potatoes and the vegetable stock, and bring to a simmer. Put on a lid and simmer for 25-30 minutes or until the sweet potatoes are really soft. Season and whizz with a stick blender until completely smooth. Keep warm.

Heat 2 tsp of oil in a frying pan and fry the remaining spring onions, ginger and garlic over a high heat for 2-3 minutes or until softened. Reduce the heat, add the kale and a splash of water, and cook for 2-3 minutes until the kale has wilted. Stir in the remaining miso and season. Spoon the soup into bowls and top with the miso kale, to serve.