In a skillet, heat 2 tablespoons of olive oil over medium heat. Once shimmers, add 1 chopped onion and sauté for about 5 minutes until translucent. Stir in 2 minced garlic cloves and cook for an additional minute until fragrant.

Add 6 cups of fresh chopped spinach along with a pinch of salt, pepper, 1/4 teaspoon of ground nutmeg, 1 teaspoon of dried oregano, and 1 teaspoon of dried dill. Cook for about 3-4 minutes, until wilted. Remove from heat and let cool slightly.

In a mixing bowl, combine the cooled spinach mixture with 1 cup of ricotta cheese and 1/2 cup of crumbled feta cheese. Stir until creamy and well mixed.

Preheat oven to 400°F (200°C) and line a baking sheet with parchment paper. Roll out 2 sheets of puff pastry to a light thickness and cut into 12 equal squares.

Place a tablespoon of filling in the center of each square. Fold each square diagonally to form triangles and press edges tightly. Use a fork to crimp edges.

Beat one egg to create an egg wash. Brush the tops with the egg wash and sprinkle seeds on top if desired.

Bake for 20-25 minutes, until puffed, golden brown, and crispy. Watch closely in the last few minutes for the perfect finish.

Cool on a wire rack for a few minutes and serve warm.