Preheat the oven to 400°F.
In a large skillet, heat the grape seed oil over a medium flame and cook the onions until translucent; about 5 minutes. Add in the spinach and minced garlic and keep over a medium flame until the spinach has reduced and wilted.
Add the whisked eggs and olives to the skillet and cook until the eggs have set. Stir occasionally to prevent the eggs from burning and to allow even cooking; season with salt and pepper.
Remove the skillet from the heat; stir in the thawed cream cheese and mix well. Transfer the egg mixture to the fridge and allow it cool while prepping the pastry dough.
Using a baking sheet lined, preferably, with a Silpat, roll out the puff pastry dough and cut it in half, so you have two individual pastry sheets approximately 12” wide by 5” high.
Place half of chilled egg mixture into the center of the pastry dough leaving a 1-inch margin on the top and bottom and a 3-inch margin on both the left and right sides of the filling sprinkle the feta cheese on top of the filling. Repeat with the second pastry dough.
Slice the left and right margins into ½-inch strips at about a 45° angle. Fold the top left strip across followed by the top right strip across continuing in this fashion and creating a “braided” look.
Once all the strips have been “braided” mix 1 egg with water and give the pastry a quick brush with the egg wash; bake in the oven for about 30 minutes, or until the pastries have reached a nice golden brown. Serve warm.