1. Rinse and drain rice 3 times or until water runs clear. Place rice in sieve over a bowl. Set aside for 10 minutes to drain.
2. Place the in a small saucepan with 240ml of water, and cook over medium heat, covered. Once boiling, reduce the heat to low & Simmer, for 12 minutes - until water has been absorbed. Remove from the heat. and leave to stand, covered, for 10 minutes.
3. Transfer rice to alarge bowl & stir rice to break up lumps. Gradually add seasoning, lifting and turning rice, until rice has cooled.
4. Marinade the chicken with 2 tablespoons of sweet chilli sauce in a small bowl.
5. Heat oil in a small frying pan over medium-high heat. Add the chicken & cook for 5 minutes turning to ensure meat is cooked throughout. Meanwhile, combine the mayonnaise and remaining sweet chilli sauce in a small bowl.
6. Place one nori sheet, shiny-side down, on a sushi mat. Leaving a 2cm strip at 1 long end, spread 1/4 rice mixture over nori using damp fingers. Spread 1/4 mayonnaise mixture across centre of rice. Arrange 1/4 chicken, avocado, cucumber and lettuce over rice.
7. Using mat, roll up firmly to form a roll. Cut roll into 6 slices. Repeat with remaining nori sheets, rice mixture, mayonnaise mixture, chicken, avocado, cucumber and lettuce to make 24 pieces. Serve.