Preheat your oven to 350°F (175°C) and lightly spray a 9×13 inch baking dish with nonstick cooking spray.

In a large mixing bowl, combine the yellow cake mix, eggs, vegetable oil, and water. Stir until well combined.

Pour the batter into the prepared baking dish and bake for approximately 30 minutes, or until a toothpick inserted into the center comes out clean. Let the cake cool for 10 minutes.

Using a wooden spoon or skewer, poke holes in the cake at about 1-inch intervals.

In another bowl, whisk together the instant vanilla pudding mix, cold milk, vanilla extract, and fine salt until it reaches a thick, creamy consistency. Let it stand for 5 minutes.

Pour the pudding mixture generously over the warm cake, allowing it to seep into the holes. Cover with plastic wrap and let it chill in the refrigerator for at least 2 hours.

In a small saucepan, heat the heavy cream over medium heat until steaming. Remove from heat, pour it over the semi-sweet chocolate chips, and whisk until smooth.

Add corn syrup (if using), vanilla extract, and a pinch of salt for balance.

Once the cake has chilled, drizzle the chocolate ganache evenly over the top and refrigerate again for 30-60 minutes.

Top with whipped topping and garnish with chocolate curls or shaved chocolate before slicing into square pieces. Serve chilled.