Preheat oven to 350°F (175°C) and grease a 9x13 inch baking pan.

In a large mixing bowl, combine the German chocolate cake mix, melted butter, and 1/2 cup of evaporated milk until a thick, uniform dough forms.

Press half of the cake dough into the bottom of the prepared baking pan to form an even layer.

Bake the bottom layer for 8 to 10 minutes.

While the base is baking, combine the unwrapped caramels and the remaining 1/3 cup of evaporated milk in a heavy saucepan over medium-low heat, stirring constantly until melted and smooth.

Remove the pan from the oven and sprinkle the chocolate chips and chopped pecans evenly over the partially baked base.

Pour the melted caramel mixture over the chocolate chips and pecans.

Crumble the remaining cake dough over the top of the caramel layer.

Return the pan to the oven and bake for an additional 18 to 20 minutes.

Remove from the oven and allow to cool completely at room temperature, then refrigerate for at least 2 hours to ensure the caramel is set before slicing into bars.