1. Fill a medium pan with water, cover and bring to the boil. Add half the pack of pad Thai noodles to the boiling water, then simmer for 3-4 mins, till soft. Drain the noodles, rinse them with cold water the drizzle over 1 tbsp oil and gently toss to lightly coat in the oil. Set to one side.
2. While the noodles cook, trim the roots and top 3cm off the leek. Halve it, rinse out any grit and finely slice it. Trim and thinly slice the carrot (no need to peel it). Tear the mushrooms into small pieces. Pat the tofu dry, then chop or tear it into chunks – they don't have to be the same size.
3. Pop a deep frying pan or wok on a medium-high heat and tip in the peanuts. Toast for 2-4 mins, shaking the pan regularly till the nuts are golden. Tip them onto a chopping board and set aside to cool.
4. Set the pan back on the heat and pour in 1 tbsp oil. Add the tofu and fry for 5 mins, turning occasionally, till golden and crisp.
5. While the tofu cooks, finely chop the chilli, halving it and flicking out the white pith if you prefer less heat. Scoop the chilli into a bowl and stir in the tamari, 1 tbsp fischy sauce and 1 tbsp Demerara sugar.
6. When the tofu has fried for 5 mins, add the leek, carrot and mushrooms to the pan and fry for 6 mins, stirring often, till the veg has softened but still has a bit of bite. Meanwhile, roughly chop the peanuts.
7. When the veg has cooked for 6 mins, add the noodles to the pan along with the chilli and tamari mixture and half the peanuts. Toss everything together to warm the noodles through. Taste and add a pinch of salt if you think it needs it.
8. Divide the noodles and veg between a couple of bowls. Top with the remaining peanuts to serve.