Preheat the oven to 400°F/205°C. Line a baking sheet with parchment paper and set aside.
Drizzle olive oil over the asparagus, and season with salt and pepper.
To make the cream mixture, in a bowl combine the cream cheese with garlic powder, salt, and pepper. Give it a quick mix so that everything is well combined.
Unfold the thawed puff pastry on a lightly floured surface and roll into a 10 inch x 14-inch rectangle. Transfer to the prepared baking sheet, then using a sharp knife score the edges leaving a 1-inch border. Then using a fork, prick the puff pastry sheet.
Spread the cream cheese mixture over the puff pastry sheet inside the border, then sprinkle with gruyere cheese.
Top the cheese with the asparagus spears arranging them to be parallel with each other. Brush the border/edges with an egg wash.
Bake for 20-25 minutes or until the puff pastry is puffed and lightly browned.
Remove from the oven, cut into 6-8 squares, and serve warm or at room temperature.