01 - Preheat oven to 400°F. Line a rimmed baking sheet with parchment paper and set aside.
02 - Unroll the thawed puff pastry onto the prepared baking sheet. Using a sharp knife, score a ¾-inch border around all edges without cutting through the dough. Prick the interior area generously with a fork to prevent puffing. Brush the scored border evenly with beaten egg.
03 - In a mixing bowl, combine softened goat cheese, crème fraîche, minced garlic, and lemon zest. Season with salt and pepper. Stir until completely smooth and well blended. Spread the filling in an even layer within the scored border of the pastry.
04 - Toss trimmed asparagus spears with olive oil, a pinch of salt, and pepper. Lay the spears in a neat, even arrangement over the cheese filling, pointing them in the same direction.
05 - Bake on the center rack for 30 to 35 minutes, until the pastry border is deeply golden and puffed and the asparagus is tender with light charring at the tips.
06 - Remove from the oven and scatter fresh thyme leaves over the top. Allow the tart to rest for 5 minutes before slicing into portions. Serve warm or at room temperature.