Preheat the oven to 190°C (375°F) and grease a baking dish with olive oil

Heat 2 tablespoons extra virgin olive oil in a large skillet over medium heat

Add the finely chopped onion and sauté until translucent, about 4–5 minutes

Stir in the minced garlic and cook until fragrant, about 30 seconds

Add the chopped spinach in batches, stirring until wilted and cooked down

Remove the skillet from heat and let the spinach mixture cool slightly

In a large mixing bowl, combine the cooked spinach, crumbled feta cheese, beaten eggs, chopped dill, chopped parsley, sea salt, and black pepper; mix gently

Unroll the thawed phyllo dough sheets and cover them with a slightly damp kitchen towel to prevent drying

Place one sheet of phyllo dough in the bottom of the greased baking dish and brush lightly with olive oil

Repeat layering and brushing oil on 5–6 sheets of phyllo to create the base

Spread the spinach and feta filling evenly over the layered phyllo

Continue layering the remaining 4–5 sheets of phyllo on top, brushing each sheet lightly with olive oil

Tuck in any overhanging edges and lightly score the top layer with a sharp knife to create serving portions

Bake in the preheated oven for 30–35 minutes, or until the phyllo is golden and crisp

Remove from the oven and let cool slightly before cutting and serving