Preheat Oven and Prepare Cake Mix: Preheat your oven to the temperature specified on the cake mix box (most likely 350° F). In a large bowl, combine the cake mix, 1 cup of water, 3 large eggs, and ½ cup of vegetable oil. Mix until smooth and combined.
Bake the Cake: Pour the batter into a greased 9x13 inch baking dish. Bake according to the package instructions, usually for around 25-30 minutes. Test the cake's readiness by inserting a toothpick into the center; it should come out clean when the cake is done. Remove the cake from the oven and let it cool slightly.
Poke and Soak the Cake: Once the cake is slightly cooled, use the end of a wooden spoon to poke holes all over the cake. Melt the semi sweet chocolate chips in a microwave safe bowl, once melted add the sweetened condensed milk to the melted hocolate and stir together until fully combined. Pour the chocolate sweetened condensed milk all over the cake, aiming to fill the holes. Set aside.
Prepare Chocolate Pudding Layer: In a medium bowl, whisk together the cold whole milk and the instant chocolate pudding mix until smooth and thick. Pour this mixture everly over the cake, spreading over the top to create a second layer.
Add Mint Layer: In another bowl, combine the thawed Cool Whip with the green food coloring and mint extract. Adjust the color and flavor to your preference. Spread this minty Cool Whip layer evenly over the chocolate layer on the cake.
Garnish and Chill: Sprinkle the chopped Andes Chocolate Mint Candies over the top of the cake. Drizzle chocolate syrup over the cake for an extra chocolatey touch. Refrigerate the cake for at least an hour to allow it to set (can set overnight).
Serve: Once chilled and set, slice the cake and serve. Enjoy the delicious combination of chocolate and mint in every bite!