Combine soy, garlic, sesame oil and chilli flakes in a bowl large enough to hold the lamb, turn the lamb in the marinade. Marinate for 1 hour or refrigerate overnight if time allows.
Wash rice and cook according to packet directions.
Preheat a BBQ to hot and cook lamb, with BBQ lid down for 10 minutes on each side or until it measures about 55°C on a meat thermometer. Transfer to a clean plate, cover loosely with foil and rest for 10 minutes before slicing into 2cm dice.
Place rice in a large bowl and add capsicum, tomato, avocado, spring onion and ½ cup chopped coriander. Squeeze over the juice of one lemon and 1-2 teaspoons soy sauce. Stir gently to combine and divide between serving bowls.
Top rice bowls with lamb, sprinkle with extra spring onions, chilli flakes and serve with lemon wedges.
You can also cook the lamb in a preheated oven at 180-200°C fan forced for 20-25 minutes.
If you are preparing your salad ingredients ahead of time, toss the avocado in some lemon juice so it doesn't go brown.
Try with lamb leg steaks or lamb eye of loin (backstrap)