Preheat your oven to 400 degrees. Line a 9X13 pan with foil and lightly spray with cooking spray.
In a medium bowl, beat the brown sugar and the next 4 ingredients (through baking soda) until thoroughly combined. Mix in the flour, ground pecans and oats until crumbly. Scoop out 1 cup and set aside. Place the remaining crumbs into your prepared pan and press down firmly to coat the bottom.
Toss the apples in a large bowl with the salt and cinnamon. Arrange them over the crust.
Drizzle the warm homemade caramel over the top and then sprinkle with the remaining crumbs you set aside.
Bake for 35 to 40 minutes until bubbly and the apples are just tender. Remove and let cool until they are just warm to the touch.
Cut into squares. Try and let the bars rest until the caramel has set before serving.