Preheat your oven to 375°F (190°C). Grease a 9×13 inch (23×33 cm) baking dish.
In a large skillet, heat the olive oil over medium heat. Add the chopped onion and garlic, and sauté until softened, about 5 minutes.
Add the chopped spinach to the skillet and cook until wilted, about 3-4 minutes. Remove from heat and let cool slightly.
In a large mixing bowl, combine the crumbled feta cheese, ricotta cheese, grated Parmesan cheese, beaten eggs, chopped dill, salt, pepper, and ground nutmeg. Mix well.
Add the cooked spinach mixture to the cheese mixture and stir until evenly combined.
Layer half of the phyllo sheets in the prepared baking dish, brushing each sheet with melted butter or olive oil before adding the next one. Make sure to let the edges hang over the sides of the dish.
Spread the spinach and cheese mixture evenly over the phyllo layer.
Layer the remaining phyllo sheets on top of the spinach mixture, again brushing each sheet with melted butter or olive oil. Fold the overhanging edges of the bottom phyllo sheets over the top layer to seal the casserole.
Brush the top layer of phyllo with melted butter or olive oil.
Using a sharp knife, score the top of the casserole into squares or triangles, being careful not to cut all the way through.
ADVERTISEMENT
