01 - Preheat oven to 350°F. Lightly grease a 13x9 inch rectangular baking dish.
02 - In a large skillet over medium heat, warm 2 tbsp olive oil and sauté onions until soft and translucent, about 5 minutes. Add spring onions and cook 2 more minutes.
03 - Add spinach in batches if using fresh, and cook until wilted and any liquid has evaporated. Remove from heat; stir in dill, parsley, and mint. Let cool slightly.
04 - In a bowl, combine feta, ricotta, eggs, salt, pepper, and nutmeg. Add cooled spinach mixture; mix well.
05 - Cover the phyllo dough with a damp towel to prevent drying while you work.
06 - Place one sheet of phyllo in the baking dish, brush with olive oil and/or melted butter. Repeat with 6-8 sheets, brushing each with oil or butter mixture.
07 - Spread the spinach filling evenly over the layered phyllo sheets.
08 - Layer remaining phyllo sheets on top, brushing each with oil or butter. Tuck in edges and brush the top generously.
09 - Score the top layers with a sharp knife into serving-sized squares or diamonds before baking.
10 - Bake for 45-50 minutes until golden and crisp throughout.
11 - Let cool for 10 minutes before slicing along scored lines. Serve warm or at room temperature.