Brush both sides of the fish filets with the olive oil.
In a small bowl, combine the butter, garlic, parsley, thyme, black pepper, salt, white pepper, and nutmeg. Mix until ingredients are fully incorporated.
Spread the butter mixture on both sides of the fish filets and place them in a greased baking dish. Pour the white wine over the top of the fish.
Bake for 15 minutes or until fish is cooked through.
Remove fish from oven and cool completely.
Roll out the puff pastry and cut into four equal pieces. Place one fish filet on each piece of pastry and fold up the edges to enclose the fish.
Brush the pastry with the lightly beaten egg.
Bake for 25 minutes or until the pastry is golden brown.
Serve warm.
Interesting Facts
Fish Wellington is a classic British dish that originated in the 19th century.
The original recipe called for beef filets, but today it is often made with fish or other types of seafood.
The white wine adds a nice depth of flavor to the dish.