Cook the loin in the oven with a drizzle of oil. Cut it into slices once cold. Boil water and a teaspoon of sesame oil and add the miso and soy sauce, a teaspoon each. Once the broth is ready, strain it. Cook the noodles separately. Put them in a bowl and add the loin, hard-boiled egg, mushrooms, a kale leaf, bean sprouts and boiling broth. Slice a spring onion and put it on top. If you like, add some fresh ginger.