Heat oil in a large deep frying pan.
Add onion and cook for 5 minutes, then add capsicum, chilli and nutmeg and cook for a further 3-4 minutes or until onion and capsicum are soft.
In the meantime, score a cross in the base of each tomato, cover with boiling water for 30 seconds then plunge into cold water. Drain and peel away the skin from the cross. Cut each tomato into quarters. Peel bananas and cut into chunks on the diagonal.
Put swordfish steaks into the pan on top of onions and capsicum and scatter tomato and banana over the top. Pour coconut milk into pan and season to taste with sea salt and cracked black pepper. Cover and cook gently for 15 minutes or until the fish is cooked through. Garnish with coriander leaves.
When the swordfish is ready it should feel firm to touch.