Preheat the oven to 350F. Prepare an 8x8-inch baking dish with parchment paper and non-stick spray.

In a large bowl, mix together the melted butter, cake mix, oats, brown sugar and eggs. Dough will be very thick, use those biceps. Add in the chocolate chips and chopped walnuts.

Press half the dough into the prepared pan and bake for 10 minutes.

While that's baking, make the caramel sauce. In a microwave safe bowl, mix the caramel bits and milk together and heat in 30 second intervals in the microwave. Stir until completely melted and combined.

Pour the caramel over the base layer. Carefully place bits of the remaining dough over the caramel, covering it completely.

Bake for another 15 minutes. Cool Completely. Keep in the fridge to keep the caramel firm and allow to come to room temperature if you want softer caramel center.