Preheat the oven to 375 F.

Peel, core, and quarter the apples. Put them in a (ungreased) baking dish just large enough to hold them in a crowded single layer. (I find that a 9×13 dish is perfect.) Toss with a little salt and 1 teaspoon of the sugar. (Unless they are very sweet, in which case you might not need any sugar at all.) If they are tart enough to make you squint, use 2 teaspoons of sugar. Dot the apples with butter, cover tightly with aluminum foil, and bake until the apples start to soften, about 15 to 30 minutes. Remove the foil, raise the heat to 500 F, and return the pan to the oven. Leave the apples to dry out and color slightly, about 10 minutes more. When the tips of the apples are golden and the fruit is tender, remove the pan from the oven, and coarsely mash the apples. (You could use a potato masher, but I just use the back of a wooden spoon, and I leave mine very chunky.)  If you like, season the applesauce further with salt and sugar to taste, and then consider a splash of apple cider vinegar to brighten the flavor. (You can try a drop on a spoonful to see if you like it; I haven’t found that my applesauce needs it.)