PREHEAT oven to 400°F.
IN a small bowl, mix together 6 oz. of cream cheese and 1/2 cup of mayonnaise until smooth. Set aside.
IN a large bowl, mix together salmon, onions, celery, pimentos, peas, parsley, dill and lemon zest. Mix with the cream cheese mixture. Taste and season with salt and pepper.
SPRAY a sheet pan with nonstick cooking spray. Lay 1 sheet of puff pastry on pan.
MOUND the salmon filling evenly across from one side to the other side, about 2 inches from the bottom end. Wrap the pastry over the top. Pinch the bottom and top pastry, rolling to seal it closed. Brush pastry with beaten egg and refrigerate for 15 minutes before baking.
BAKE for 25 minutes. Remove from oven and let rest 10 minutes before serving.
WHILE the pastry is baking, make the sauce. With a fork or hand mixer, blend 6 oz. of cream cheese with 1/2 cup mayonnaise until combined. Mix in the cucumber.
SLICE salmon and serve with sauce. Enjoy!