How to Make It
Preheat the oven to 425°. Let the fish stand at room temperature for 20 minutes. Meanwhile, in a bowl, mix the salt with the egg whites until it is the texture of moist sand.
Brush a baking sheet with oil. Set the fish on parchment paper and outline it; cut out the template, set it on the baking sheet and brush with oil. Sprinkle some of the salt mixture onto the parchment. Brush the fish all over with oil and set it on the salted paper. Stuff the fish with the parsley, garlic and lemon. Mound the remaining salt over the fish, lightly packing it. Using a skewer, poke a hole through the salt at the thickest part of the fish near the head.
Bake the fish for 25 minutes, until an instant-read thermometer inserted into the fish through the hole registers 135°. Let stand for 10 minutes. Crack the salt and discard it. Brush off any excess salt. Remove the skin and fillet the fish. Transfer to a platter, drizzle with olive oil and serve.