Combine olive oil, juice of 1 orange, mustard, salt and pepper in a jug.
Cook brown rice following packet directions. Slice carrots and add to rice for last 8 minutes of cooking time. Drain.
Preheat oven to 180°C. Heat a chargrill pan over medium-high heat until hot. Spray chicken breast fillets with olive oil spray. Cook on chargrill for 4 minutes each side. Transfer to a tray and place in oven for 10 minutes.
Spray corn cobs with olive oil. Cook on chargrill for 8 minutes. Cool. Remove kernels by running a sharp knife down the length of the corn. Combine rice, carrot, corn, spring onions and parsley in a serving bowl. Slice chicken and arrange on top of salad with avocado. Pour over dressing.