Preheat oven to 350 °F (177 °C) and grease a 8x8-inch baking pan. Set aside.
In a food processor, combine flour, oats, brown sugar, butter, baking soda, salt, and vanilla until the mixture resembles coarse crumbs.
Set aside about 1 1/2 cups of the crumb mixture. Pour remaining crumb mixture to the bottom of the prepared pan and spread evenly. Press the crumb mixture down.
Using an offset spatula, spread the apple butter in an even coat on top of the crumb crust. Then drizzle the salted caramel sauce on top (it doesn't have to be even or perfect. It's thick so it won't cover the whole thing. The idea is to have bites of the salted caramel within the bars.)
Finally, with the reserved crumb mixture, crumble it on top of the filling.
Bake for 30-35 minutes or until golden brown. Cool completely before slicing into squares