Carmelized Onion Goat Cheese Tart

Every now and then I open up the freezer and decide what can stay and what most go. I do this mostly so I can close the freezer door.  Where does it all come from?  Anyway, I found a sheet of puff pastry left over from the holidays and knew it must be used.  One cannot let a piece of delicious puff pastry go to waste.

As I had just finished watching the wonderful movie, Julie and Julia, I was in the mood to cook something French and chose to make a sort of French tart with caramelized onions and goat cheese.  This is a extremely simple dish to put together and the results are superb.
Caramelized Onion Goat Cheese Tart

3 ounces goat cheese, crumbled into small pieces
1 sheet of puff pastry, thawed at room temperature
1 large onion, cut into thin slices
1/4 cup Parmesan Cheese
Salt and Pepper to taste
Olive oil
1 egg beaten with a Tbsp of water or milk

Preheat oven to 425 degrees.  Roll out puff pastry until it's approximately 14 inches long and 8 inches wide.  Put on ungreased baking sheet.  With a pastry brush, paint around the edges of the pastry and then fold the edges over approximately 1/2 inch.  Put baking sheet in refrigerator while cooking onions.
Put approximately 1 Tbsp. of olive oil in a heavy saute pan and heat.  Cut onion into thin slices. Put in saute pan and cook, stirring frequently until they are a dark golden brown. Season with salt and pepper.  Let cool slightly. 
Distribute onions over cold puff pastry.  Top with crumbled goat cheese then Parmesan cheese.  Drizzle entire thing with some olive oil.  Brush edges with egg wash.   Bake for 15 to 20 minutes until puffed and golden brown.