For the spicy soup base, heat a 2 litre/3½ pint capacity wok until smoking and add the groundnut oil. Add the chillies and Sichuan peppercorns and stir fry for a few seconds, or until fragrant.
Stir in the chilli bean sauce and chilli sauce and then pour in the vegetable stock. Add the star anise, Chinese mushrooms, tangerine peel, spring onion, ginger and chillies and bring to the boil, then reduce the heat to low and simmer for 20 minutes.
Ten minutes before serving, add the chilli oil, the sliced Chinese cabbage, deep-fried tofu, fresh tofu and fish balls, if using.
For the vinegar, chilli and soy dipping sauce, combine all the dipping sauce ingredients together in a small bowl and set to one side.
For the Taiwanese dipping sauce, combine all of the dipping sauce ingredients together in a small bowl and set to one side.
To serve, arrange the lamb, prawns, tofu, mushrooms and fishcakes on separate plates. Transfer the soup base to an electric wok or fondue and set it up in the centre of the table. Let guests help themselves and cook the ingredients in the spicy broth. Serve with the dipping sauces.