Prepare the Filling

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Sauté Onions and Garlic: In a skillet, heat a bit of olive oil over medium heat. Add the chopped onion and garlic, cooking until soft and fragrant (about 5 minutes).
3. Prepare Spinach: If using fresh spinach, rinse and chop it, then add it to the skillet, cooking until wilted. If using frozen spinach, make sure it’s thoroughly drained and add it directly.
4. Mix the Filling: In a large bowl, combine the spinach mixture with feta, ricotta, beaten eggs, dill, salt, and pepper. Mix until well combined.

Assemble the Pie

1. Prepare the Phyllo: On a clean surface, lay out the phyllo dough. Keep the unused sheets covered with a damp towel to prevent drying.
2. Layer Phyllo Sheets: Brush a 9-inch pie dish with melted butter. Place one sheet of phyllo dough in the dish and brush with butter. Repeat, layering about 6 sheets, brushing each with butter.
3. Add the Filling: Spoon the spinach mixture into the phyllo-lined dish, spreading it evenly.
4. Top with Phyllo: Layer additional phyllo sheets on top, brushing each with butter. Fold the edges over the filling to create a sealed pie.
5. Score the Top: Lightly score the top layers of phyllo with a knife to create serving pieces.

Bake the Pie

1. Bake: Place the pie in the preheated oven and bake for 30-35 minutes, or until the top is golden brown and crispy.
2. Cool and Serve: Remove from the oven and let it cool for a few minutes before slicing. Serve warm or at room temperature.