01 - Preheat the oven to 350°F.
02 - Heat olive oil in a large skillet over medium heat. Cook the onion for 3 to 4 minutes until softened, then add the garlic and cook for an additional minute.
03 - Add the spinach to the skillet and stir until wilted and excess moisture evaporates, approximately 5 minutes. Remove from heat and allow to cool slightly.
04 - In a mixing bowl, combine crumbled feta, ricotta, eggs, dill, parsley, nutmeg, salt, and pepper. Fold in the cooled spinach mixture, mixing thoroughly.
05 - Brush a 9-inch pie dish with melted butter.
06 - Arrange 4 filo sheets in the dish, brushing each layer with melted butter and allowing the edges to overhang the sides.
07 - Distribute the spinach and feta mixture evenly over the layered filo base.
08 - Top the filling with the remaining 4 filo sheets, brushing each with melted butter. Fold the overhanging edges over the top and brush with additional butter.
09 - Use a sharp knife to lightly score the top filo sheet to permit steam to escape during baking.
10 - Bake in the preheated oven for 35 to 40 minutes, until the filo is golden brown and crisp.
11 - Allow the pie to rest for 10 minutes before slicing and serving.