Place juice or water in a large stock pot. (Either one will help prevent browning.) Bring it to a gentle simmer. Begin to peel the apples; don’t worry about getting the stem or blossom ends perfectly peeled.
On the larger holes of a box grater, grate the apple on a small cutting board down to the cores. Add the grated apples to the stock pot as you go, stirring them in to prevent browning. A potato masher helps to break the apples down
When all of the apples are grated, increase the heat and add more liquid if needed. Once the sauce has cooked down to your preferred consistency, add sugar and/or spices to taste. A hand blender can be used at this point if you desire a very smooth sauce. Cool and divide the sauce into freezer containers/zipper lock bags. Alternately, you can use a water bath canner to preserve it in mason jars.