In large saucepan, combine 3/4 c. sugar, the cornstarch, water & salt. Cook over medium heat, stirring constantly until thick.
Remove from heat & add the rest of sugar, butter, cinnamon & nutmeg. Using a whip, beat until smooth & mixed thoroughly.
Add peeled, sliced apples that have been generously sprinkled with lemon juice, to make the prepared sauce nice & thick with apples. May need more.
Place pie filling in prepared crust.
Place top crust on & flute. Cut slits on top for ventilation. Spread on softened butter, then sprinkle with sugar.
Cover edges of pie with foil or crust shields & bake @ 375° for 25 minutes. Remove foil or covers & bake 20-25 more minutes until crust is a golden brown & flaky!. Allow to cool or serve warm with ice cream.
INSTRUCTIONS FOR CANNING:
Place in wide mouth quart jars. I fill a little over 2/3 full, as it expands some. Heat lids & place on jars & hot bath for 30 minutes. 1 jar will make a regular size pie. 3 jars will make 2 deep dish pies.