Rinse and wipe-dry a lime; Bisect the lime lengthwise with a knife; Place each halved lemons over the doom of a lemon squeezer and then press and twist to extract the juice.
Add seasonings and the lime juice into a mixing bowl; Mix.
Hold a flathead mullet firmly by the head and scrape the scales from the tail towards the gills with a fish scaler; Rinse the fish under running water; Insert the knife into the anus near the tail; Draw the knife toward the head, splitting the fish to the base of the gills; Spread the abdominal cavity with fingers; Reach in and pull out the entrails; Rinse the cavity under running water; Cut off the head with the knife; Rinse the fish under running water again; Pat-dry the fish with kitchen paper; Rub the seasoning mixture into the fish evenly; Wrap the fish with baking paper completely.
Rinse and drain coriander; Cut off any root and stem.
Pre-heat an oven to 150 degree Celsius.
Add 3750g coarse sea, 3 tsp Sichuan pepper and 3 star anises salt into a dry wok; Stir-fry over a medium heat till they are thoroughly hot; Pour 1 cup of oil into the mixture; Stir-fry it over a medium heat till well-mixed; Turn off the heat.
Line a piece of aluminum foil on a baking pan draping the corners over the sides; Evenly spread the salt mixture from the step 6 over the foil; Arrange the wrapped fish in the center; Flip 2 sides of the foil to cover the fish wrapped and turn the remaining 2 sides to cover the wrapped fish completely; Put it in the oven and bake it for 45 minutes; Take the fish out of the oven; Discard the foil, the salt mixture and the baking paper; Arrange the fish on a serving plate; Garnish it with the coriander; Ready to serve.