Prepare the Filling

1. Sauté Vegetables: Heat olive oil in a large pot over medium heat. Add chopped leeks and cook until soft and translucent, about 6-7 minutes.
2. Cook Spinach: Add chopped spinach to the pot, stirring frequently, until it wilts and most of the liquid evaporates.
   • Pro Tip: If there’s excess moisture, transfer the mixture to a colander and press out the liquid.
3. Combine Ingredients: Remove from heat and let the mixture cool slightly. Stir in crumbled feta, salt, and black pepper. Taste and adjust seasoning as needed.

2. Preheat the Oven and Prep the Dish

1. Preheat your oven to 375°F (190°C).
2. Lightly grease a baking dish with olive oil.

3. Layer the Phyllo Dough

1. Bottom Layers: Place two-thirds of the phyllo sheets in the dish, brushing each layer generously with olive oil.
   • Pro Tip: Arrange sheets with some edges overhanging the sides to fold over the filling later.
2. Add Filling: Spread the spinach and feta mixture evenly over the phyllo layers.

4. Add the Top Layers

1. Fold the overhanging phyllo edges over the filling.
2. Layer the remaining phyllo sheets on top, brushing each with olive oil.
3. Tuck the edges of the top phyllo layers neatly around the filling.
4. Lightly score the top layers with a knife to create serving portions, being careful not to cut through to the filling.

5. Bake the Spanakopita

1. Sprinkle the top with 2 tablespoons of water to help the phyllo crisp up during baking.
2. Place the dish on the lower rack of the oven and bake for 60 minutes, or until the top is golden and flaky.
3. Let cool for 30 minutes before slicing into squares or triangles and serving.