Yeah this is that recipe - the one you've seen all over Pinterest & beyond. My version is fairly similar but I've made 2 small changes that make a big impact. First, I use Dulce de Leche caramel - a mild milk caramel that is not overly sweet. Trader Joe's stocks their own nowadays and it works very well. But you can easily make your own or use another variety. La Salamandra is much pricier because it is imported from Argentina, but equally good.
The second and most crucial consideration is the salt itself. I only use Fleur de Sel, a French Sea Salt characterized by broad flat flakes. It is often used by chefs as a garnish since it considered a finishing salt. It truly makes all the difference. And it is so important, I don't even attempt this recipe unless I have it on hand.
For Crust & Crumble
2 cups (1 pound) salted butter, room temp
1 cup sugar
1 ½ cups powdered sugar
2 tablespoons vanilla extract
4 cups all-purpose flour, sifted
For the Filling:
2 jars (16 oz.) Trader Joe's Dulce de Leche Caramel
1 tablespoon Fleur de Sel Salt
Preheat the oven to 325°. Line a 9x13 baking pan with parchment paper.
In a large bowl combine butter and sugars, mix on medium speed until creamy. Add the vanilla and beat until combined. Slowly add the flour to the butter mixture on low speed and mix until a smooth, soft dough forms. Press 1/3 of the dough into the prepared baking pan, and bake in preheated oven for 20 minutes or until the edges are a pale golden brown. Refrigerate the remaining 2/3 of the dough.
If you are going to make your caramel from candies, do that while the crust bakes. Place the unwrapped caramel candies and cream in a microwave safe bowl and microwave on high for 1 minutes. Stir until smooth. If the caramels are not completely melted, continue microwaving on high heat for 30 second intervals, stirring after each one. Once the caramels are melted, stir in the vanilla. Set aside until the bottom crust is done baking.
Pour the caramel filling over the crust, sprinkle with salt and crumble the remaining dough over top. Continue baking until the filling is bubbly and the topping is firm and lightly golden, about 25-30 minutes. Let cool before cutting into squares.