Instructions:

1. Preheat Oven: Preheat your oven to 400°F (200°C).
2. Prepare the Puff Pastry: Roll out the puff pastry on a lightly floured surface and place it on a baking sheet. Use a knife to lightly score a 1-inch border around the edges, being careful not to cut through the pastry.
3. Make the Filling: In a small bowl, mix ricotta, Dijon mustard, salt, and pepper. Spread this mixture within the scored border of the puff pastry.
4. Assemble the Tart: Lay the asparagus spears evenly across the pastry, alternating directions. Tear the prosciutto into smaller pieces and place it between the asparagus spears. Sprinkle shredded Gruyère cheese over the top.
5. Brush the Edges: Brush the edges of the puff pastry with beaten egg.
6. Bake: Bake for 20-25 minutes, until the pastry is golden brown and the asparagus is tender.
7. Serve: Slice and serve warm as an appetizer or light main course

Enjoy!