Preheat oven to 425 Fahrenheit.
Line a baking tray with aluminum foil.
Grease the the foil by spraying cooking oil spray all throught.
Meanwhile, brush the melted butter on the fish and then sprinkle the lemon pepper seasoning all over the fish (swai fillet). Arrange the fish over the aluminum foil.
Bake for 10 minutes.
Remove from the oven and transfer to a serving plate.
Serve. Share and enjoy!