Preheat oven to 350℉ and line a 9” x 13” pan with parchment then grease with cooking spray. In a large bowl using a hand mixer, beat butter and sugar together until light and fluffy. Add flour and salt and mix until just combined.
Press into the prepared pan about ½” up the sides. Bake until lightly golden, 20 minutes.
In a large bowl, toss apples, lemon juice, brown sugar, cinnamon, vanilla, and salt together. Spread apples over the crust.
In a medium bowl, whisk together flour, pecans, brown sugar, and salt. Stir in melted butter until coarse clumps form.
Sprinkle crumb topping over the apples and bake until the top is golden and apples are soft, about 1 hour.
Let cool for at least 15 minutes then slice into squares and drizzle with caramel before serving.