Preheat the oven to 400 degrees. Line a baking sheet with parchment paper.
Once puff pastry has thawed, gently roll it out into a rectangle. Use a sharp knife to score a border 1 inch from the edge of the pastry. Don't cut through the pastry, but enough that the line is visible. This will allow for the border of the pastry to puff up.
Then use a fork to prick the pastry inside the border. This will stop the puff pastry from rising in the center.
In a small bowl combine the dijon mustard, honey, cream, salt and pepper. Spread over the center of the puff pastry.
Sprinkle the shredded cheese in the center of the pastry.
Rinse the asparagus and trim off the woody ends. Layer the spears of asparagus on top of the cheese.
Bake for 20-25 minutes or until golden brown. Let sit a minute or two before slicing into 9 squares.
Gruyere cheese can be replaced with swiss or mozzarella.
Honey and cream can be omitted or the cream can be replaced with milk.
It will change the taste, but spicy brown mustard can replace dijon mustard.
Let your puff pastry thaw out on the parchment you are using to bake it on. It's easier than trying to move it.
After the pastry has thawed for 5-7 minutes, you should be able to gently unfold it from the trifold and lay it flat, removing the small strips of paper it comes frozen with.