01 - Preheat oven to 400°F and line a baking sheet with parchment paper.
02 - Roll out puff pastry onto the prepared baking sheet. Using a sharp knife, lightly score a 1/2-inch border around the edges without cutting through. Prick the center area with a fork.
03 - In a mixing bowl, combine crème fraîche, goat cheese, egg, Parmesan, lemon zest, herbs, salt, and pepper. Whisk until smooth and well incorporated.
04 - Spread the cheese mixture evenly over the center of the pastry, keeping within the scored border clear.
05 - Arrange zucchini, asparagus, red onion, and cherry tomatoes decoratively over the cheese base. Drizzle with olive oil and season with additional salt and pepper.
06 - Bake for 25-30 minutes until pastry is golden and crisp and vegetables are tender.
07 - During the last 5 minutes of baking, scatter spinach leaves over the tart allowing them to wilt slightly.
08 - Remove from oven and let cool for 5 minutes before cutting into portions. Serve warm.