Add the oil to a hot pan set over a medium / high heat. Add the onion and sauté until slightly softened. Add the pancetta, reserving a quarter, and the potatoes.
Cook until the pancetta is crisp and the potatoes start to soften.
Pour over the stock and drop in the bay leaf.
Simmer, covered, until the potatoes are fully cooked (dropping off a knife).
Remove half of the potato, pancetta and onion with a slotted spoon and set aside. Discard the bay leaf.
Add the soup along with the milk to a food processor and blend until smooth.
Meanwhile, add the fish, prawns and corn to the pan over a medium heat. Pour over the soup, and add the reserved potato mixture. Add the pinch of mace.
Simmer, covered, until fish is cooked – the white fish should be opaque, flaky and moist. Do not boil!
Add cream, salt and pepper to taste.
To serve, ladle into bowls and sprinkle with chives and the remaining crispy pancetta.