Put apple pieces in a large, deep pot and toss with lemon juice.
Add water
Over high heat, bring to a boil, stirring.
Reduce heat to medium, and cook, stirring occasionally, until apples are soft, about 10 minutes.
Use an immersion blender in the pot to puree the apples.
Keep sauce at a gentle boil while ladling into hot, sterilized jars.
Wipe jar rims with a damp paper towel, and put lids and bands on jars.
Process jars in a boiling-water canner for 20 minutes.
Allow jars to cool, making sure they are sealed, and store in the pantry until ready to use.
Notes
Jars and bands can be reused, but new lids are required.Check each jar for any chips or nicks and do not use those for processing.Sterilize the empty jars for ten minutes in the water bath canner you are using for processing, keeping the water simmering so that it's ready to bring to a boil for processing the filled jars.Cooking time for the apples will depend on how big your pieces are. Larger pieces will require longer cooking time.Use a canning funnel to fill the jars with hot applesauce.When filling the jars, leave ½ inch headspace.Use a damp paper towel to wipe the rims of the jars clean before applying the lids.If you don't have an immersion blender, transfer cooked apples to a blender or food processor in batches. Then return pureed apples to the pot and bring back to a gentle boil before ladling into jars.If you prefer to add cinnamon, put a cinnamon stick in the pot with the apples, then remove it before transferring the sauce into jars.Prep time given is for peeling and coring apples by hand, and if you have an apple peeler / corer, it will be much reduced.For even more apple flavour, substitute the water for apple juice or apple cider.If you prefer not to process your applesauce, it will keep in the fridge for about a week, and can also be frozen.You can add sugar if you want this unsweetened applesauce recipe to be a sweet applesauce. Add sugar in ¼ cup increments, tasting until it's as sweet as you like. Sugar should be added after the apples are pureed and brought back to a boil.If you like a chunky, rather than a smooth applesauce, coarsely crush half the cooked apples and puree the other half before combining them.