Always start by making sure you have 6 clean and sterilized quart jars, lids, and bands ready. You don’t want all your hard work to be wasted on dirty jars.
Peel and core apples. (An old fashioned apple peeler/corer is an essential tool for all apple cooking. If you don’t have one, get one.)
Cut the apples into small triangles or long slices.
Pre-fill the jars with apples to make sure you have enough apples cut for 6 quart jars. Then empty them into a large bowl and set aside.
In a large pot add the sugar, cinnamon, nutmeg, cornstarch, salt and water.
Bring the mixture to a boil on high heat, stirring frequently. Boil for just 1 minute. The sauce will thicken and become clearer.
Remove from heat, add lemon juice, and stir.
Using a jar funnel and ladle, switch back and forth pouring sauce and apples for even mixing. Fill the jars full of pie filling up to 1/2′ from the lip.
Seal the jars with lids and bands.
Place the jars in a boiling canning pot for 20 minutes to fully process.