This can be made with any ripe fruit. If you like your fruit leather entirely smooth, you can remove the skins, but you can leave them in for the nutritional value. Remove any stems, seeds or bruised areas. Be creative with spices and flavorings - apples or pears go marvelously with a pinch each of nutmeg and cinnamon, while cherries and peaches both love almond or vanilla extract. Add sweetener if the fruit needs it. The cooking time will vary widely depending on the ripeness and water content of the fruit - it's done when it is barely tacky to the touch and peels easily off the sheet. Keeps 2 weeks at room temperature, 3-4 months in refrigerator, 2 years in freezer. Adapted from a recipe by Carolyn Cope at Serious Eats.