Preheat oven to 400 ℉.
Remove puff pastry sheet from freezer and let defrost for 1 hour covered with parchment paper or paper towel.
Make sure the salmon is clean and deboned and the skin is removed.
Roll out puff pastry pieces into one big sheet using a rolling pin. Cut sides to make an even square or rectangle.
In a bowl combine all ingredients: salt, black pepper, garlic powder, fresh garlic, parsley, olive oil, and lemon juice.
Prepare a baking sheet with 1 sheet of parchment paper.
Place puff pastry over parchment paper.
Place salmon over puff pastry sheet. Then, using a paring knife cut into ½” strips on both sides of the salmon. Try to cut even strips on both sides.
Using a basting brush, or spoon, pour ingredients onto the salmon.
Grab strips on each side and crisscross.
To make eggwash, beat one whole egg with 1 tbsp of cold water.
When all pieces have been crisscrossed, using a basting brush take eggwash and brush over the entire surface of the puff pastry. Sprinkle chopped parsley, fresh or dry for garnishing if desired.
Place in the middle of the oven for 12-15 minutes. Then place on top rack for an additional 5 minutes or until puff pastry is golden brown.