If you are making your own applesauce, cut up about 6 apples and place them in a medium saucepan. I like to cut my apple slices thin (about 1/4 inch thick) to help it cook down quicker. Add water, sugar, and cinnamon to the apples. Stir to combine and cook on medium heat. Let the apples cook down until softened, about 30 minutes. At this point, you can either leave the applesauce chunky or use an immersion blender or blender to puree the apples. Let the applesauce cool while you are getting ready to assemble the applesauce cake.