If you're baking with a dark non-stick pan, heat your oven to 325°F. Grease a 9×13-inch baking dish with non-stick spray to make sure the cake slides out easily when it’s done.
Prepare the cake mix according to the package directions but add a special touch by folding in fresh lemon juice and lemon zest.
Pour the cake batter into your greased pan and spread it out evenly.
Bake in the oven for approximately 25 to 30 minutes. Check if it's fully baked by inserting a toothpick into the middle—if it comes out clean, you're all set.
Allow the cake to cool for a few minutes after baking, then use a fork, skewer, or similar tool to create lots of holes across the top. More holes mean the jello seeps in deeper and makes it even more flavorful.
Stir the lemon jello into hot water in a separate bowl until it’s fully dissolved, then mix in the cold water.
Carefully pour the lively jello mixture over the cake, filling each hole.
Seal the cake with plastic wrap and let it refrigerate for a minimum of 1 hour and 30 minutes. This step is key, as it gives the cake time to soak up all the lemony goodness.
To make the frosting, whisk the heavy cream, powdered sugar, lemon pudding mix, and a splash of vanilla extract in a big bowl.
Whip it up until it’s thick, light, and fluffy, it should hold stiff peaks when it’s ready.
Once your cake is chilled and the frosting is perfectly whipped, spread it over the top. Take your time and make it look as gorgeous as it tastes.