3 cups sliced peeled apples, 1 1/4 cups water, 2/3 cup sugar, 1/2 cup cornstarch, 1/2 t. salt, 1 1/2 t. cinnamon, 1 1/3 cups undiluted Carnation evaporated milk, 2 beaten eggs, 1 1/2 t. vanilla, 1/3 cup packed brown sugar, 1/4 cup flour, 1/4 cup quick oats, 1/2 t. nutmeg, 3 T. butter, 1 9" baked pie crust.
Cook apples in 1/2 cup boiling water in covered saucepan 10 minutes. Drain.
Combine sugar, cornstarch, salt and 1 T. cinnamon in a medium saucepan. Stir in evaporated milk and remaining 3/4 cup water. Cook over medium heat, stirring constantly until mixture comes to a boil and thickens. Stir small amount into eggs and empty into custard mixture stirring to blend. Return to heat and cook stirring constantly, just until mixture comes to a boil. Stir in vanilla and cook slightly.
Next combine brown sugar, flour, oats, 1/2 t. cinnamon and nutmeg in a small bowl. Cut in butter. Place apple slices in bottom of the pie crust. Pour custard over apples. Sprinkle brown sugar mixture over top. Bake in a preheated 350 degree oven for 15 minutes. Cool, then chill in frig for a least 2 hours or more before serving. Can make a day ahead.