Fill your kettle and boil it. Fill a large pan with the hot water from the kettle, topping it up with extra water if needed, and add a pinch of salt. Cover and bring the pan back to the boil.

Meanwhile, drain the tofu, pat dry with kitchen paper and then slice into chunks around 1cm thick. Trim and peel the red onion, then finely slice it. Trim and finely slice the celery stick. Halve the green pepper, scoop out the seeds and white pith, and roughly chop the pepper. Tear any of the larger mushrooms into smaller pieces.

Warm a wok or deep frying pan on a medium-high heat. Add ½ tbsp oil and the tofu. Fry for 2-3 mins, turning once, till the tofu is lightly browned.

Scoop the tofu out of the pan, add another ½ tbsp oil and all the chopped veg. Stir fry for 5 mins till the veg have started to soften but still have a bit of crunch to them. Fill and boil the kettle again.

Check the pan of water. The water should be boiling by now. Add the noodles and simmer for 8 mins till the noodles are tender but still have a little bite to them.

Return the tofu to the pan with the veg, add the teriyaki sauce and pour in 150ml boiling water. Stir to mix, then simmer for 3-4 mins.

When the noodles are cooked, drain them and shake dry. Add them to the veg and tofu and toss together. Divide the dish between 2 warm plates or bowls and serve.