Preheat the oven to 350 degrees F (175 degrees C). Lightly grease a 9x13-inch baking dish.

Make cake mix according to package directions. Pour a little less than 1/2 of the batter into the prepared dish.

Bake in the preheated oven for 15 minutes. Remove cake from the oven.

Place caramels, milk, and butter in a microwave-safe bowl and cook on high, stirring occasionally, until melted and smooth, about 10 minutes. Pour melted caramel mixture over cake and sprinkle with pecans and chocolate chips. Pour remaining cake batter over the top.

Bake in the preheated oven until the center of cake bounces back when gently pressed, 20 to 35 minutes.