Soak the shitake mushrooms in a saucepan of hot water for 45 minutes. Strain them and cut into small dice.
Carefully wash the lettuce leaves and thinly slice.
Carefully wash the tomatoes and cut them into small dice.
Heat 1 litre of water and dilute the stock cube. As soon as the water is simmering, add the mushrooms, tomatoes, lettuce, chilli sauce, soya sauce and ginger.
Meanwhile, make an omelette with the eggs. Cut the omelette into small pieces and add it to your soup.
Cook for a few minutes and then serve.