1. Preheat the oven to 350°F (or 325°F for dark or nonstick pans) and grease a 13×9-inch baking pan to prevent sticking.
2. Prepare the cake mix as directed on the box by combining water, vegetable oil, and eggs, then mix until smooth. Pour half of the batter into the prepared baking pan.
3. Bake the first layer of the batter in the oven for about 12-15 minutes to allow the base to firm slightly.
4. While the cake is baking, melt caramels with evaporated milk (and optional butter) in a saucepan over medium-low heat or in the microwave, stirring until smooth.
5. Remove the partially baked cake from the oven and evenly pour the melted caramel mixture over the baked layer.
6. Sprinkle the caramel layer with chopped pecans and semisweet chocolate chips to add crunch and richness.
7. Carefully pour the remaining cake batter over the toppings, fully covering the caramel, pecan, and chocolate layer.
8. Place the pan back in the oven and bake for an additional 20-28 minutes, ensuring the cake is fully set in the middle.
9. Once baked, allow the cake to cool in the pan on a wire rack to set the layers and make cutting easier.
10. Serve the cake as it is or enhance it with additional toppings such as caramel sauce, extra chopped pecans, or a scoop of vanilla ice cream for a delicious finish.