• Preheat oven to 400°F.

For the Crumb Mixture:

• Mix brown sugar, butter, and shortening in a large bowl or in the bowl of a stand mixer.
  1 cup packed brown sugar, ½ cup 1 stick butter , ¼ cup vegetable shortening
• Stir the flour, the oats, salt, and baking soda. Reserve 2 cups oat mixture; press remaining oat mixture in ungreased, 13 x 9 x 2-inch rectangular pan.
  1 ¾ cups all purpose flour, 1 ½ cups quick cooking oats, 1 teaspoon salt, ½ teaspoon baking soda

Make Filling and Assemble Bars:

• Toss apples and 3 tablespoons flour; spread over mixture in pan.
  4 ½ cups chopped, peeled tart apples, 3 tablespoons all purpose flour
• Heat caramels over low heat, stirring occasionally, until melted; pour evenly over apples. Alternatively, evenly disperse caramel bits over the apples.
  1 bag 14 ounces caramels, unwrapped
• Sprinkle reserved oat mixture on top; press lightly.
• Bake 25 to 30 minutes or until topping is golden brown and apples are tender (mine took about 35 minutes). Cut bars while warm. Store covered in refrigerator.