Spray a 9x13 baking dish with cooking spray. Set aside.
In a large mixing bowl, mix cake mix, water, vegetable oil and eggs. Mix until well combined or there is no more dry flour. Scrape the sides of the bowl as needed.
Pour your cake batter into the baking dish and bake in preheated oven for 25 to 30 minutes. The sides of the cake will be slightly separating from the baking dish and the center of the cake should spring back when you touch it.
Once cake is baked, set aside until completely cool. This will take 1-2 hours.
Once the cake is cool, use a straw or the end of a wooden spoon and poke some holes throughout the cake. This will help the vanilla/lime pudding to get more into the cake.
In a large mixing bowl, add dry vanilla pudding, lime juice, milk, heavy cream and lime zest. Whisk together quickly until it is completely combined and smooth.
Pour the pudding mixture on top of the cake and use a spatula to spread evenly. Place the cake in the fridge while you make the whipped cream.
Making the whipped cream is easiest with a stand mixer or a hand mixer. Place the heavy cream, salt, powdered sugar and vanilla extract in the mixing bowl. Beat on high speed until the mixture forms stiff peaks.
Gently spread the whipped cream over the top of the cake so the cream and pudding don’t mix together. Apply gentle pressure but don’t push down too much.
Decorate as you'd like with slices of lime and lime zest.
Keep in the refrigerator until you serve.
The calories shown are based on the cake being cut into 15 pieces, with 1 serving being 1 slice of cake. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information. The information in the nutrition box are calculated through a program and there is room for error. If you need an accurate count, I recommend running the ingredients through your favorite nutrition calculator.**