Preheat the oven to 350°F (175°C). Grease the 9x13 inch baking dish with non-stick spray or butter.
In a large mixing bowl, combine the chocolate cake mix, instant chocolate pudding mix, eggs, milk, and vegetable oil. Whisk until well combined and smooth.
Pour the cake batter into the prepared baking dish, spreading it evenly.
Sprinkle the chocolate chips over the top of the cake batter.
Carefully pour the boiling water over the entire mixture. Do not mix; this is essential to create the gooey layer.
Bake in the preheated oven for 45 minutes or until the edges are set, and a toothpick inserted in the center comes out slightly moist but not wet.
Allow the cake to cool for about 10 minutes before serving. Optionally, dust with powdered sugar for extra sweetness.
Serve warm with a scoop of vanilla ice cream for an extra treat.