Half-fill a medium pan with water and bring to the boil. Rinse the quinoa in a fine sieve, then add to the water, stir well and simmer for 12 mins or until just tender.
While the quinoa is cooking, put the sweetcorn in a dry frying pan over a medium-high heat. Cook for 5 mins, turning every now and then, until defrosted and lightly toasted. Set aside.
Rinse the cooked quinoa in a sieve under cold water, then press hard with a serving spoon to remove excess water.
Tip the quinoa into a bowl and toss with the olive oil, sweetcorn, tomatoes, coriander, spring onions, lime zest and chilli. Season well with black pepper.
Halve and stone the avocado. Scoop out the flesh with a large metal spoon, cut into slices and combine with the lime juice. Add the chicken pieces and avocado to the salad and toss gently together before serving.