1 C brown sugar
1/2 C oats (quick or old fashioned)
1/2 t salt
3/4 C (stick and a half) butter, melted
4 C peeled, sliced apples (I like Granny Smiths)
1 T cornstarch
3/4 C white sugar
1/4 t salt
1/2 C water
1/2 t vanilla
Combine first 5 ingredients and stir until blended. Measure 1 1/2 C of this mixture and set aside for topping. Press remaining mixture in bottom and up sides of 9 in. pie plate. Arrange apple slices in plate and set aside.
Combine white sugar, cornstarch and salt (1/2 t) in saucepan. Whisk in water. Cook over medium heat until mixture boils. Remove from heat and add vanilla. Pour hot mixture over apples. Crumble reserved topping over pie. Bake at 375 for 30 minutes. Then, cover with foil and bake 15 more minutes.