Put all the ingredients for the dressing in a large bowl and mix until smooth.
To cook the noodles, bring three litres of water to a rolling boil, add a tablespoon of salt and mix. Drop in the noodles, stir vigorously to stop them from sticking, then cook according to the packet instructions, moving them around with a fork or tongs to stop them from sticking together.
Drain, rinse under cold water until really cold, then drizzle over a couple of tablespoons of oil and toss or stir to coat.
Add the cold noodles to the dressing bowl, then tip on to a large platter and arrange the vegetables and tofu in little piles around the outside, and sprinkle liberally with toasted sesame seeds.
Toss everything together at the table, then divide into four individual bowls.
