In a mixing bowl, combine cream cheese, Parmesan, mayonnaise, garlic powder, onion powder, and pepper. Mix until smooth and well combined.

Squeeze the thawed frozen spinach to remove excess moisture, then fold it into the creamy mixture.

Lightly flour your countertop and unroll the puff pastry sheet. Spread the spinach dip filling over the pastry, leaving a thin edge at one end.

Starting from the filled edge, carefully roll the pastry into a tight log and pinch to seal the seam and ends.

Wrap the rolled pinwheel log tightly in plastic wrap and refrigerate for at least 30 minutes.

Preheat your oven to 400°F (200°C).

Once chilled, slice the pinwheel log into half-inch thick pieces and place them cut-side up on a baking sheet.

In a small bowl, beat the egg with a splash of water and apply the egg wash over the tops and sides of the pinwheels.

Bake the pinwheels for 15-20 minutes until they puff up and turn golden brown.