Place the first pie crust on a well-floured surface and roll into a 1/8-inch thickness. With a 3-inch heart-shaped cookie cutter, cut 12 to 14 hearts from the rolled crust. Transfer the hearts to a plate or baking sheet and place in the refrigerator, then roll and cut the second crust. After cutting both crusts, you should have 24 to 28 hearts total.
In a small bowl, stir together the pie filling and lemon zest. Set aside.
Place racks in the upper third and center of the oven, then preheat the oven to 400 degrees F. Line to baking sheets with parchment paper or silicone mats.