For the best results, use a mandoline to slice the apples paper-thin.
TO MAKE THIS CAKE, YOU WILL NEED:
24 tablespoons (3 sticks) unsalted butter, softened
3 cups (12 ounces) confectioners’ sugar2 tablespoons heavy cream2 teaspoons vanilla extract⅓ teaspoon salt1 recipe Salted Caramel Filling*, cooled2 (9-inch) Applesauce Cake Layers*2 Fuji, Gala, or Pink Lady apples, cored, quartered, and sliced very thin2 tablespoons granulated sugar2 tablespoons lemon juice
FOR THE FROSTING:
Using stand mixer fitted with whisk attachment, whip butter on medium-high speed until smooth, about 20 seconds. Reduce speed to low and slowly add confectioners’ sugar, cream, vanilla, and salt. Whip until sugar is moistened, about 1 minute. Scrape down bowl and add ½ cup caramel filling. Whip on medium-high speed until light and fluffy, about 4 minutes, scraping down…
