Preheat oven to 350F. Prepare cake mix as instructed on box. Pour 1/2 of the batter into greased 10 x 13 inch baking pan. Bake until center is not liquid, about 15-20 minutes. Do not cook completely. While cake is in oven, place caramels and butter in microwave. Heat until butter is melted and caramels just start to melt.
Pour in condensed milk. Heat in microwave until well blended, stirring continually, so caramel does not scorch. When cake is ready, pour caramel mixture over it, then pour remaining batter on top. Sprinkle with chocolate chips and pecans. Bake until top layer is done, about 10-15 minutes. Cut into squares after cooled.
Cajun Country -- New Iberia, Louisiana