For the Shortbread Crust:

1. Preheat oven to 350°F. Line a 9x13 pan with foil and spray thoroughly with nonstick spray.
2. In a medium bowl, mix together flour and powdered sugar for crust.
3. Cut in butter (I use my hands, you could also use a fork or a food processor) until the mixture forms a dough. Pat it into a 9x13 pan.
4. Bake crust for about 10 minutes, until puffed and golden around the edges. Remove from oven while you prepare brownie batter.

For the First Brownie Layer:

1. In a large bowl, prepare both boxes of brownie batter as instructed on the box.
2. Pour HALF of the batter over the shortbread crust and spread evenly.
3. Bake for about 20 minutes – brownies should be set, but still a bit gooey in the center. Let cool for 10 minutes.

For the Caramel:

1. In a microwave safe bowl, heat caramel bits and heavy cream, stopping to stir every 30 seconds until smooth.
2. Pour melted caramel over brownie covering as much as the surface as possible.

For the Second Brownie Layer:

1. Evenly spoon remaining brownie mix over the surface of the caramel.
2. CAREFULLY spread the brownie mix to cover. You may get a bit of caramel that oozes up over the surface -- this is okay. The brownie batter will puff up in the oven to cover any caramel that is showing.
3. Bake for roughly 20 minutes, until brownies are set and a toothpick inserted in the center comes out with caramel or fudgy crumbs but NO raw brownie batter.
4. Let brownies cool to room temperature, then refrigerate until firm.
5. Grabbing the ends of the foil, remove brownies from pan.
6. Peel off the foil and cut into squares and serve.