Take frozen spinach and drain it very well. Sauté the onion and leek first, then add the spinach for a light sauté. Add salt and pepper, and when you remove it from the heat, add the eggs and cheese and mix well.

Lay one sheet of puff pastry in a baking dish, spread the filling on top, and cover with the second sheet. Brush the top sheet of the pie with an egg and score into pieces. Bake at 350°F until golden brown.