I learned this trick when I worked at a bakery! Just add spinach to puff pastry!

A mouthwatering savory pie made with flaky puff pastry, filled with tender ham, melted mozzarella, and fresh spinach, finished with a subtle tangy touch of mustard. Ingredients: Puff pastry — 1 sheet / pack Mustard Spinach Ham Mozzarella cheese Egg yolk — 1 Milk — 1.5 tbsp