Store-bought pastry from the freezer case makes the buttery base for the leek tart. Scoring the dough defines the border, and pricking prevents the center from puffing up too much during baking.
- All-purpose flour, for work surface
- 1 sheet store-bought puff pastry (from a 17.3-ounce package), thawed
- 2 tablespoons butter
- 6 leeks (white and light-green parts), halved lengthwise and thinly sliced crosswise, rinsed well
- Coarse salt and ground pepper
Preheat oven to 375 degrees. On a lightly floured work surface, roll pastry to a 10-by-14-inch rectangle. Halve lengthwise into two 5-by-14-inch rectangles. Transfer to a baking sheet lined with parchment paper.
With a paring knife, lightly score each rectangle 1/2 inch from edges, creating a border; prick pastry inside border all over with a fork. Refrigerate for 15 minutes, then bake until golden brown, 18 to 20 minutes. (To store, keep crusts at room temperature, up to 1 day.)
In a large skillet, heat butter over medium. Add leeks; season with salt and pepper, and stir. Cover; cook until wilted, about 5 minutes. Uncover; cook until tender, 10 to 12 minutes. Spoon leeks onto crusts, cut tarts into wedges, and serve.