In a large bowl, combine the flour, oats and brown sugar. Cut in butter until crumbly. Reserve 1 cup for the topping. Stir in chips to the remaining mixture. With floured fingers, press into a greased 13-in. x 9-in. baking pan. Bake at 350° for 15-18 minutes or until golden brown.
In a large bowl, beat cream cheese until light. Add the milk, lemon juice and vanilla; beat until smooth. Pour over the crust. Combine the cornstarch and cranberry sauce until blended. Spoon over the cream cheese mixture. Sprinkle with the reserved crust mixture.
Bake at 350° for 30 minutes or until center is set. Cool for 1 hour on a wire rack. Cover and refrigerate.