Step 1

Prepare the Curd: Whisk together lemon juice, granulated sugar, and eggs in a saucepan. Cook over medium-low, whisking constantly, until slightly thickened, about 3 minutes. Add butter a few cubes at a time, and cook, whisking constantly, until melted before adding more butter. Continue cooking, whisking constantly, until Curd is smooth and coats the back of a spoon, about 2 minutes. Pour through a fine mesh strainer into a heatproof bowl, discarding solids. Stir in zest; chill 1 hour.

Step 2

Meanwhile, prepare the Crust: Preheat oven to 350°F. Line a 13- x 9-inch baking pan with parchment paper, leaving a 2-inch overhang on all sides. Stir together crumbs, melted butter, and sugar in a medium bowl until combined. Press on bottom and ½ inch up sides of prepared pan. Bake in oven until Crust begins to brown, about 10 minutes. Transfer to a wire rack to cool slightly, about 15 minutes. Reduce oven temperature to 325°F.

Step 3

Meanwhile, prepare the Filling: Beat cream cheese and sugar in bowl of a stand mixer fitted with a paddle attachment on medium speed until smooth, about 2 minutes, scraping down sides as needed. Add sour cream, eggs, and vanilla, beating on medium speed until smooth, about 2 minutes. Pour cream cheese mixture over Crust. Using a tablespoon, dollop chilled Curd on top; swirl Curd into mixture using the tip of a knife.

Step 4

Bake at 325°F until Filling is almost set but jiggles slightly in center, 35 to 40 minutes. Transfer to a wire rack, and cool 1 hour. Refrigerate until well chilled, about 4 hours. Using the parchment paper overhang, lift cheesecake out of pan. Cut into 16 (2¼- x 3¼-inch) bars, and serve.