Cook the eggs in boiling water for 6 minutes, remove and run under cold water to cool, peel and set aside.
Meanwhile, heat the oil in a frying pan and fry the tofu for 3-4 minutes until golden and set aside on a plate.
Dissolve the stock cubes in 1.5 litres boiling water and place in a large saucepan with the miso paste and bring back to the boil, add the noodles and cook for 4 minutes, then add the beans and cook for a further 2 minutes. Stir in the spinach until wilted.
Transfer to bowls and top with the tofu, Walnuts and halved eggs. Drizzle over the soy, if using, to serve.