Preheat oven to 350F. Grease a 13x9x2-inch pan. Combine caramels and 1/3 cup of the evaporated milk in a heavy saucepan. Heat and stir until blended, keep warm
Combine the dry cake mix, melted butter and remaining evaporated milk in a bowl, mix well
Spread half of the mixture in bottom of greased pan. Bake for 6 minutes. Immediately sprinkle chocolate chips over baked cake layer; drizzle with caramel mixture.
Spread remaining cake batter evenly over top. Return to oven and bake 15 to 18 minutes more or until top is dry. Cool on rack; cut into bars.
