1 small onion, chopped
1/2 pound button mushrooms and stems, cleaned and chopped
2 sprigs dill, chopped
1/4 cup flat leaf parsley leaves, chopped (a small handful)
Juice of 1/2 lemon
1 tablespoon Dijon mustard, optional
2 hard-boiled eggs, chopped
Salt and freshly ground black pepper, to taste
4 6-ounce salmon filets, skin removed
2 sheets frozen puff pastry, 11 x 17 inches, defrosted but still cold
1 egg, beaten with a splash of water
Preheat oven to 425F.
Heat a large non-stick skillet over medium heat. Add oil, onions and mushrooms. Season with salt and pepper, and saut 10 -15 minutes or until the liquid from the mushrooms has evaporated. Remove from heat and add to a medium-sized mixing bowl. Add dill, parsley, lemon juice, mustard, hard-boiled egg, salt and pepper. Mix to combine.
Wipe out the pan you used for the mushrooms and return it to medium-high heat with a drizzle of EVOO. Season salmon with salt and pepper, and sear 1-2 minutes on each side in a drizzle of oil. Remove skillet from the heat.
Spread the puff pastry sheet onto a counter and roll to 1/8 of an inch thick. Cut in half.
On each rectangle of dough, place 2 spoonfuls of the mushroom mixture and top with salmon.
Starting with the corners, wrap dough over the salmon, creating a package.
Trim excess dough and seal with the egg water mixture using a pastry brush (leftover dough bits can be used to decorate the top of the packages).
Place sealed side down on a non-stick cookie sheet and make small slit in the top to let steam escape.
Brush with a light coating of the egg/water mixture to give it a nice sheen. Bake 10-15 minutes or until golden brown. Let stand 5 minutes, then serve.