Preheat oven to 350 degrees F. Line a 9x13-inch baking pan with aluminum foil, leaving a 2-inch overhang on each side for easy lifting later. Spray foil with nonstick cooking spray. (I used nonstick aluminum foil.)
In a large bowl, mix together flour, oats, brown sugar, baking soda, and salt. Add melted butter and mix until combined well. Spread half of the mixture in prepared pan, pressing down to cover the bottom. Bake 10 minutes. When 10 minutes are up, remove from oven but do not turn off oven.
While oat mixture bakes, place unwrapped caramels, evaporated milk, and cream in a saucepan over low heat. Stir frequently until caramels are melted and mixture is thoroughly combined.
Sprinkle chocolate chips over baked mixture and then pour melted caramel evenly over the chips. Sprinkle remaining oat mixture over caramel and bake 15 minutes.
Let cool completely in pan on wire rack. Use foil to lift out of pan and cut into bars when ready to serve.