Heat 1/4 Cup Olive Oil in a large saucepan and sauté the onions and leek until translucent, about 2 to 3 minutes. Add the spinach and sauté until the leaves have wilted and the liquid has cooked off, about 8 to 10 minutes.

Remove the pan from the heat and allow to cool somewhat. When cool enough to handle, finely chop the spinach and place in a large bowl.

Add dill and feta to spinach mixture. Add salt and pepper to taste (careful with the salt as the feta will add quite a bit of its own.) Pour the eggs over and give a stir to combine well.

Open up the phyllo pastry and place on work surface. Moisten a paper towel and cover dough to prevent it from drying out as you work. Layer the phyllo in the pan, brushing each phyllo layer generously with olive oil. Use half of the phyllo sheets to make the bottom pastry layer.

Put the spinach mixture in and press the top down gently to smooth filling. Add top layer of phyllo pastry, oiling between sheets as for bottom layer.

Using a sharp knife, score the upper layers of pastry into the size pieces you will want to serve once the pie is baked. Be careful not to cut through the bottom layer of pastry.

Bake the pie in the middle of the oven for 40 to 45 minutes until it is golden brown. Cool until just warm. Cut into serving sized pieces and serve either just warm or at room temperature.