Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.

Thaw and thoroughly drain the frozen chopped spinach, squeezing out excess moisture.

In a mixing bowl, combine the drained spinach with crumbled feta, ricotta or cream cheese, minced garlic, chopped herbs, a beaten egg, salt, and pepper. Stir until evenly mixed.

Roll out puff pastry sheets on a floured surface to an even thickness and spread the spinach and feta mixture, leaving an edge of half an inch.

Roll the pastry tightly into a log shape and slice into rounds about 1 inch thick.

Place rolls cut-side up on the prepared baking sheet and brush with egg wash; sprinkle with sesame or poppy seeds if desired.

Bake for 18-22 minutes until golden brown and puffy, then remove and allow to cool slightly before serving.