Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking dish.

In a large mixing bowl, combine ricotta cheese, sugar, and vanilla extract. Beat until smooth. Add eggs one at a time, mixing until fully incorporated.

In another bowl, combine cake mix, oil, water, and eggs. Mix until well blended.

Pour the chocolate cake batter into the prepared baking dish. Spoon the ricotta mixture on top.

Bake for 1 to 1.5 hours, checking for slight jiggle but not wet center.

Let the cake cool in the pan at room temperature for 30 minutes, then chill in the refrigerator.

Prepare the pudding frosting by mixing the pudding with whole milk, whisk until thick, then fold in Cool Whip.

Once cooled, spread the pudding frosting over the ricotta layer.

Refrigerate for at least 4 hours before serving.