Much of this information is from Carla Emery’s wonderful book, The Encyclopedia of Country Living... Wash, peel, and de-seed the fruit or fruits you’d like to use. Mash/purée it thoroughly into the texture of applesauce - it has to be thin enough to pour, but not too thin. For very watery fruits (like berries and grapes), add applesauce, or cook the mixture down to the right consistency. For too-thick purée, add a little fruit juice. (You can also make leather from dried fruits if you soak them in hot water before grinding them up into purée.)

If you wish, heat your purée to just below boiling to retard browning of lighter-colored fruits. You can also use cooked purée if that’s more convenient. (...Of course, you’ll be killing off some of the nutritive value of the fruit.) Or you might need to cook it... You can also make leather from sweet vegetables, like yams and pumpkin! - or try sweetened rhubarb - perhaps combined with applesauce? Sweeten the purée if you must (powdered sugar works well) - but most fruit is sweet enough as it is.

Spice it up too, if you like. Get creative - how about cinnamony quince or crab-apple leather with minced cranberries? Savory/herby pumpkin? Piña colada leather with apricot, pineapple, and finely-shredded coconut? - makes my mouth water to think of it!

Pour the leather onto high-quality plastic wrap in a baking pan or sheet; or onto wax paper or foil if it’s lightly sprayed with oil or a non-stick vegetable spray. Tilt the tray so as to "spread" the purée around evenly to a depth of only 1/8-1/4". (The thinner it is, the less time it takes to dry.) You can dry it in the sun, in a dehydrator, or in an oven that goes as low as 120-130 degrees. If you’re drying in the sun (which supposedly makes better-lasting, and perhaps better-tasting, leather), protect the purée with a cheesecloth tent of some sort. You need good air circulation, whatever the method; and the more humid the air, the longer the drying time. In a dehydrator or oven, shift multiple pans around to different shelves often. And always dry both sides - peel the leather from its backing and turn it over carefully.

When the leather is as dry as you like it, cut it into strips or pieces and roll them up in plastic wrap or wax paper - then store them in an airtight container (like a zip-lock bag). The less sticky the leather, the longer it can be stored unrefrigerated without molding... Or you can freeze it. (Of course you can reconstitute the fruit leather as you might any other dried fruit... But it’s such a treat to eat a sheet!)

(See also Tomato Leather)