Heat oven to 450°. Arrange fish in a shallow roasting pan lined with parchment paper, leaving a bit of space between the portions. Spoon butter or olive oil over the fish, making sure a little goes underneath. Season with salt. Cook 10 minutes per 1 inch of thickness, remove from oven, and let rest 5 minutes before serving.
In a small bowl, combine lemon, herbs, and extra-virgin olive oil. Spoon over fish before serving.