Preheat the oven to 150 degrees F (165 degrees C), or the lowest setting you have.

Combine lemon juice, apricots, and sugar in a saucepan. Cook over medium heat until sugar has dissolved. Transfer to a blender and puree until smooth.

Cover an 11x17-inch pan or cookie sheet with a layer of plastic wrap. Pour pureed fruit onto the prepared pan and spread evenly to within 1 inch of the edge.

Bake for 4 to 6 hours in the preheated oven, using a spoon or a pair of tongs to keep the door slightly ajar, or until puree has dried and is no longer sticky. Once dry, you can cut it into strips; store in an airtight container.