Preheat your oven to 400°F (200°C).

In a skillet over medium heat, add a drizzle of olive oil. Once hot, toss in the chopped mushrooms and garlic. Sauté for about 5 minutes until the mushrooms soften, then add the chopped spinach. Cook for an additional 2 minutes until wilted. Season with salt and pepper.

In a mixing bowl, combine the sautéed mixture with cream cheese and shredded mozzarella. Stir until well combined.

On a lightly floured surface, roll out the puff pastry sheet to about ¼ inch thick.

Spread the mushroom and cheese mixture evenly over the pastry, leaving a small border around the edges.

Carefully roll the pastry from one side to the other creating a log shape. Slice it into 1-inch pieces.

Place the pinwheels on a baking sheet lined with parchment paper. Lightly beat the egg and brush the tops of each pinwheel with the egg wash.

Bake in the preheated oven for 15-20 minutes or until puffed and golden. Allow to cool slightly before serving.