Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking dish or line it with parchment paper for easy removal.
In a large mixing bowl, combine the flour, oats, brown sugar, baking soda, and salt. Stir in the melted butter until the mixture is crumbly.
Press half of the oat mixture into the bottom of the prepared baking dish to form a crust. Bake for 10 minutes.
Remove the crust from the oven and sprinkle the chocolate chips evenly over the top. Drizzle the caramel sauce over the chocolate chips, then sprinkle the chopped pecans on top.
Crumble the remaining oat mixture over the pecans, covering as much of the filling as possible.
Return the baking dish to the oven and bake for an additional 15-20 minutes, or until the top is golden brown.
Allow the bars to cool completely in the baking dish before cutting them into squares. For best results, chill in the refrigerator for at least 1 hour before serving.