Preheat your oven to 400°F (200°C). Thaw puff pastry for 30 minutes, flour the surface, and roll to 1/8 inch thick.

Heat olive oil in a skillet over medium heat. Sauté spinach for 3-5 minutes until wilted, then cool and chop finely.

Mix the sautéed spinach with crumbled feta cheese until well blended.

Spread the spinach-feta mixture on the pastry and slice into 1-inch strips. Twist into spirals and arrange on a baking sheet.

Whisk the egg in a bowl and brush it over the top of each pastry twist.

Bake in the preheated oven for 15-20 minutes until golden brown and puffed. Cool slightly before serving.