In a pan, heat butter, chopped shallots, and garlic over medium heat. Sauté until the shallots become translucent.
Bring the heat to high and add the white wine. Let the liquid cook out for about five minutes, then add the cream cheese and sauté for one minute.
Lastly, add the spinach, bread crumbs, and Parmesan cheese. Sauté just until the the spinach softens.
Unfold the pizza dough onto a light floured surface and roll out the two sheets, then cut them in half. So you end up with four pieces. I made each piece about 10 by 14 inches.
Place each seasoned salmon fillet in the middle of each puff pastry sheet. Depending on the size of the fillet, you may need to roll out the puff pastry a little more or less. Leave about two inches around the edges.
Divide the spinach mixture into four equal parts and evenly spread it on top of the four fillets. Then brush the edges of the pizza dough with egg wash (one egg plus one teaspoon water).
Begin folding the the puff pastry over starting with the longer side. When folding over the short edges, brush more of the egg wash before folding.
Line a baking sheet with parchment paper and place the salmon wellington seam side down.
Make crosshatch slits on top of the Wellington with a knife. Then brush with more egg wash.
Bake at 375 degrees Fahrenheit for 25-30 minutes or until the dough is golden brown.