It's so easy to cook applesauce in the oven. Fruit is in season in autumn and if you have an apple tree in your garden, you can cook down lots of fallen fruit.
Choose aromatic, juicy apple varieties that have a slightly sour note, for example Elstar and Boskop. The riper the fruits are, the more sugar they contain, so adjust the amount of sugar in the recipe. The less sugar you use, the shorter the applesouce will last.