Cook the noodles according to the instructions on the packet, drain and set aside.
Blend the spice paste in a high-speed blender or food processor. If you don't have one, a pestle and mortar will also work.
In a large saucepan or wok, fry the spice blend for a few minutes then add the onion and mushrooms.
Stir through and heat for a further few minutes.
Add the stock and coconut milk, bring to the boil and then simmer for 10-15 minutes.
Add the spinach, tofu and the noodles and simmer for a further minute.
Remove from the heat (do not drain — it’s supposed to be a slightly soupy dish) and serve with fresh coriander and a squeeze of lime juice.
