Cook the rice as per the instructions on the packet.
Mix together the cashew butter, chilli sauce and soy sauce in a large bowl. Pour the lime juice and add the cabbage, carrot, spring onions and coriander. Toss to mix it all together.
Sprinkle the sesame seeds onto a plate and press the tuna steaks on top. Flip and repeat so both sides are evenly covered.
Heat the coconut oil in a non-stick frying pan over a high heat. Add the tuna and fry for 1 minute on each side or until cooked to your liking.