Preheat Oven: Set your oven to 350°F. Lightly grease a 9×13-inch baking dish with butter or nonstick spray.

Combine Dry Ingredients: In the prepared baking dish, whisk together the chocolate cake mix and instant chocolate pudding mix until well combined.

Add Wet Ingredients: In a separate bowl, mix the whole milk and melted butter until combined. Pour this mixture over the dry ingredients in the baking dish. Stir until just combined; it’s okay if there are a few lumps.

Add Chocolate Chips: Sprinkle the chocolate chips evenly over the top of the batter.

Bake: Place the baking dish in the preheated oven and bake for 35–40 minutes, or until the top is set and a toothpick inserted into the center comes out with moist crumbs.

Cool and Serve: Allow the cake to cool for about 5 minutes before serving. Enjoy warm, optionally with a scoop of vanilla ice cream or a dollop of whipped cream.