When selecting apples for canning, you want to choose sweet, juicy, and crisp apples.
Wash, peel, and core the apples. If you'd like, you can slice the apples into water containing ascorbic acid to prevent browning.
Place the drained slices into a large 8-10 quart pot and add half a cup of water.
Stir occasionally to prevent burning while heating the apples.
Heat them quickly, until tender. This will take anywhere from 5 to 20 minutes.
Use a sieve or a food mill to create a smooth texture, or you can bypass this step if you prefer chunk-style applesauce.
If you prefer your applesauce to be on the sweeter side, you can add 1/8th cup of sugar per every quart of sauce. Taste the sauce and add more sugar if you prefer a sweeter taste.
Reheat the sauce to boiling and fill hot sauce into pint or quart jars, leaving a half-inch headspace.
Wipe the jars clean of any residue, add the lids, and bands.
Transfer the jars to either a boiling water canner or a pressure canner. For a boiling water canner, you'll process pints for 15 minutes and quarts for 20 minutes. If you'd prefer to use a pressure canner, you'll process pints for eight minutes and quarts for 10 minutes at 6 lbs of pressure in a dial-gauge pressure canner. If you're using a weighted-gauge canner, you'll process pints for eight minutes and quarts for 10 minutes at 5 lbs of pressure.
After your processing time has finished, let the jars cool in the canner (and if you're using a pressure canner, wait for the pressure to return to zero).
Remove the jars and place them on a clean dish rag to cool at room temperature for another 24 hours.
Check the seals, label, and store. Your applesauce should be safe to eat for at least one year.