Heat olive oil in a large skillet over medium heat. Add leeks and cook until they are wilted, about 5-7 minutes, then reserve.
In a mixing bowl, whisk together cream, eggs, lemon zest, salt and pepper.
On a lightly floured surface, or between two layers of plastic wrap or parchment paper, roll out the thawed puff pastry to a thickness of about 1/4 inch (5 mm). Line a shallow 9” (23 cm) pie plate and press the pastry up the sides to make a nice edge.
Distribute leeks evenly across the bottom of the dish. Pour the cream mixture over leeks. Top the quiche with feta.
Bake 30-40 minutes until the center is firm and the crust and top are nicely browned.
Nutrients per serving:
Calories: 509 Fat: 41 g Saturated Fat: 15 g Trans Fat: 0.5 g Cholesterol: 191 mg Sodium: 625 mg Sugars: 2 g Fibre: 2 g Protein: 11 g Carbohydrate: 25 g