Start by heating 3 tablespoons of olive oil in a large skillet over medium heat. Add the chopped onion and green onion, and sauté until they are soft and translucent, about 5 minutes.
While the onions are cooking, defrost the frozen spinach and squeeze out any excess moisture. This step is crucial to prevent your spanakopita from becoming soggy.
In a mixing bowl, combine the sautéed onions, spinach, lemon juice, crumbled feta cheese, beaten eggs, ground nutmeg, and dried oregano. Stir until well combined.
Preheat your oven to 375°F (190°C). Take your phyllo dough out and place it on a clean surface. Keep the unused sheets covered with a damp cloth to prevent them from drying out.
Brush your baking dish with melted butter. Lay down 4 sheets of phyllo dough, brushing each layer with butter before adding the next. Make sure the edges hang over the sides of the dish.
Spread the spinach and feta mixture evenly over the phyllo base. If you're using Parmesan cheese, you can sprinkle it over the filling for added flavor.
Fold the overhanging phyllo dough over the filling, then layer the remaining phyllo sheets on top, brushing each with butter. Tuck in the edges to seal the filling inside.
Using a sharp knife, score the top of the pie into squares for easy slicing later. Bake in the preheated oven for about 30-35 minutes, or until the top is golden brown and crispy.
Once baked, let the spanakopita cool for a few minutes before slicing. Serve warm and enjoy the delightful flavors of your Easy Spanakopita Recipe (Greek Spinach Pie).
