The filling. Shred the spinach, dill and parsley. Finely chop the garlic and scallions.
Heat the olive oil in a medium saucepan over medium heat. Add the scallions and garlic and cook, stirring continuously, until soft, for about 2-3 minutes. Add the spinach and herbs in batches and cook until wilted. Drain, remove from heat and let cool.
Crack the eggs into a bowl and beat well. Crumble in the feta cheese and season with black pepper. Mix in the spinach and herbs.
The pastry. Lightly butter a 9x13 inch (23x33cm) baking pan. Put the first sheet of phyllo dough inside and brush it with butter. Let the excess hang over the sides. Repeat until half of the dough is used up. Preheat the oven to 325°F (160°C).
Spread the spinach and feta filling evenly over the layers of phyllo. Continue layering the remaining sheets brushing each one of them with butter. When all the dough is used up, fold over the excess pastry from the side. Brush the top with the remaining butter.
Bake for about 1 hour or until golden brown. Enjoy!