In a large bowl, whisk together the lemon pudding mix and cold milk for about 2 minutes until the pudding begins to thicken.
Gently fold in the whipped topping until the mixture is smooth and well combined.
2. Layer the Cake
In a 9×13-inch baking dish, arrange a layer of graham crackers on the bottom, breaking them as needed to fit.
Spread half of the lemon pudding mixture evenly over the graham crackers.
Add another layer of graham crackers on top of the pudding layer.
Spread the remaining lemon pudding mixture over the second layer of graham crackers.
Top with a final layer of graham crackers.
3. Frost the Cake
Microwave the lemon frosting for about 15-20 seconds to make it easier to spread, being careful not to overheat it.
Pour the softened frosting over the top layer of graham crackers and spread it evenly with a spatula.
4. Chill the Cake
Cover the baking dish with plastic wrap and refrigerate for at least 4 hours, or preferably overnight. This allows the graham crackers to soften and all the flavors to meld together.
5. Serve
Once chilled, slice into squares and serve cold. Enjoy this creamy, tangy, and refreshing no-bake dessert!
