Add the dried shiitake mushrooms to a bowl, and add the beer and boiling water, ensuring the mushroom are just covered in liquid. Cover tightly with cling film, and leave to soak for around 20 minutes, or until completely soft. Drain, and set aside.
Meanwhile, heat a dash of oil in a saucepan or deep frying pan. Add the sliced greens, and cook over a medium heat for a few minutes until slightly softened. Add the garlic, ginger, vegetable stock, miso and dried noodles, along with the soaked shiitake mushrooms. Bring to a simmer, and cook for a few minutes until the noodles are fully cooked.
Serve the soup topped with some sliced spring onion, a pinch of chilli and garlic salt, a dash of hot sauce, and some dried seaweed flakes.