Lightly grease a baking dish with vegetable oil, then place the white fish fillets inside. Sprinkle both sides of the fish with salt and a touch of ground white pepper to enhance the flavor. Bake in a preheated oven at 180°C (350°F) for 15 to 20 minutes, or until the fish flakes easily with a fork. Keep in mind that exact timing may vary depending on the thickness of the fillet and your oven's performance.

Meanwhile, squeeze the juice from the lemon and finely chop the parsley or spinach leaves.

In a medium-sized skillet, melt the butter over medium heat. Once melted, add the lemon juice and stir gently to blend.

Toss in the capers and chopped herbs, stirring the mixture for about 30 seconds until the aroma develops and the ingredients are well combined.

Once the fish is done, transfer it to a plate and spoon the warm butter-caper sauce generously over the top. Serve immediately for best flavor and texture.