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Heat the oil in a wok or large frying pan over a medium heat and stir-fry the ginger onion and shiitake mushrooms for 2 minutes. Add the water bring to the boil and add the dried mushrooms, straw mushrooms, bamboo shoots, spring onions, chilli and stock.
Bring to the boil and simmer gently for 30 minutes, then add the peas and heat them through. Cook gently for 3 minutes, then slowly stir in the vinegar/cornstarch mixture until the soup thickens.
Remove the chilli (or not) and garnish with chopped spring onions before serving.
I used to make pseudo chicken noodle soup when I was ill but one day I tried hot and sour soup at a chinese restaurant instead and my cold basically disappeared the next day - amazing stuff and tastes great.
It's the ginger, garlic, black pepper and a touch of vinegar that does it. Just increase garlic, ginger, vinegar & chilli proportions according to how bad your cold is.
posted by Mr Falafel