2) Roast for 35 to 40 minutes, until the chicken is just cooked. Set aside until cool enough to handle. Remove the meat from the bones, discard the skin, and shred the chicken in large bite-sized pieces.
3) Blanch the asparagus in a pot of boiling salted water for 3 to 5 minutes until crisp-tender. Plunge into ice water to stop the cooking. Drain. Cut the peppers in strips about the size of the asparagus pieces. Combine the cut chicken, asparagus and peppers in a large bowl.
4) Pour the dressing over the chicken and vegetables. Add the spring onions and sesame seeds and season to taste. Serve cold or at room temperature.
For the Chinese dressing:
1) Whisk together all of the ingredients for the dressing and set aside until ready to use.