Heat the oven to 350°F (175°C). Grease a 9-by-13-inch baking pan and line it with parchment if desired.

Stir together the dry German chocolate cake mix, melted butter, and 1/3 cup evaporated milk until a thick dough forms. Press about half of the dough into the prepared pan.

Bake the base for 10–12 minutes, just until it begins to set. While it bakes, melt the caramels with the remaining 1/3 cup evaporated milk over low heat, stirring frequently until smooth.

Remove the partially baked base from the oven. Sprinkle the milk chocolate chips over it, then pour the warm caramel mixture evenly across the surface.

Flatten pieces of the remaining dough between parchment sheets or with lightly greased hands. Arrange the pieces over the caramel, then bake for another 20–25 minutes until the top is set and lightly browned.

Cool the brownies thoroughly for at least 30–60 minutes before cutting. Refrigerate them briefly for cleaner slices and a firmer caramel layer.