Mix apples, sugar, cornstarch, vanilla, and sugar for the filling. Place it in the bottom of a greased baking dish.
Combine all ingredients for the crumb topping, and use your fingers to mix it all together with the oil. Sprinkle over the apples and baking in the oven for about 35 minutes, until the crumb topping has turned golden brown.
Serve with whipped cream or ice cream if desired.
NOTE: Tina suggests if you do not have berries on hand, or if you just prefer apples, than you may substitute. Also, the original recipe called for almonds, I replaced with rolled oats.