Preheat the oven to 375°F. Line a baking sheet with parchment paper.
Carefully unfold the puff pastry sheet onto a lightly floured work surface. Using a rolling pin, gently roll the puff pastry into a large rectangle, approx 12 x 16 inches in size.
Carefully transfer the puff pastry to the prepared baking sheet. Use a sharp knife to score a 3/4" border around the edge of the puff pastry; do not cut all the way through. Use a fork to prick holes inside the border of the puff pastry; place the sheet pan into the freezer to chill the pastry dough, 15-20 minutes.
Meanwhile, in a small bowl, combine the ricotta and goat cheese in a small bowl; reserve.
Trim the ends of the zucchini, then using a vegetable peeler, cut the zucchini lengthwise into long, thin ribbons. Place the zucchini ribbons into a large bowl; sprinkle with a bit of kosher salt and freshly ground pepper, tossing gently to combine.
When the pastry dough is chilled, return the baking sheet to your work surface. Spread the prepared ricotta/goat cheese mixture evenly over the pastry, leaving the border exposed. Place the zucchini ribbons on top, then drizzle the ribbons with a bit of good olive oil.
Bake the tart, uncovered, on the center oven rack until the crust is very puffed and golden brown, and the zucchini is softened, 35-40 minutes. Allow the tart to cool slightly before slicing. Serve warm or at room temperature.
Notes
Tips for Working With Puff Pastry To thaw puff pastry, remove it from the package, wrap in plastic and thaw in the refrigerator overnight. Or, thaw on the cupboard for 20-30 minutes, taking care not to let puff pastry get to warm to work with. Be sure the puff pastry sheets are fully thawed before you try to unfold them. If you begin unfolding the puff pastry and it tears, this is a sign it's not ready to cooperate just yet. Once the pastry has fully thawed, it will easily unfold for you. Puff pastry will keep in the fridge for only about 2 days. Store in the freezer for up to 6 months. Keeping puff pastry on hand in your freezer allows you to have an appetizer, as in the case of this zucchini tart, OR a tasty dessert ready in only minutes. And, because of the magic "puffiness" of puff pastry, it also looks quite impressive.