Preheat oven to 350°. Grease 12 (2 1/2-inch) wide-mouth canning jars with a paper towel dipped in oil.
Sift flour, baking powder, salt, nutmeg, allspice, cinnamon, and baking soda into a large bowl.
Using the electric mixer and a medium mixing bowl, cream together the shortening and sugar on low speed, then increase to medium mixing speed to mix well. While the mixer is running, add the eggs, one at a time. Stop the mixer and scrape down the sides.
Remove the bowl from the mixer and stir in the applesauce. With a large spoon, stir in the sifted flour mixture and the walnuts.
Pour the batter into a measuring cup with a spout; pour the batter neatly into greased jars. Fill the jars halfway full. Place the filled jars on the sheet tray and bake on the center rack of the oven for 45 minutes. When done, the top of the cake will spring back when pressed with a finger, and the sides will have come away from the jar.
Remove from oven and let cool 5 minutes. Poke holes in the cake with a toothpick and pour salted caramel over the top. Serve with whipped cream.
Adapted from Riki Senn at Greenbriar