Preheat oven to 350°. In a large bowl, toss apples, pecans, sugars, cinnamon, vanilla, and a pinch of salt together.
Pour apples into a 9”-x-13” baking dish. Top with cake mix, then place butter all over top.
Bake until top is golden and apples are tender, 50 to 60 minutes.
Serve warm with ice cream.
