01 -
Lightly spray a 9x13-inch baking dish with nonstick cooking spray.
02 -
Line the bottom of the baking dish with one layer of whole graham crackers, fitting approximately 9 crackers per layer.
03 -
In a large mixing bowl, combine cold whole milk and instant lemon pudding mix. Blend with a handheld mixer on medium speed for 1½ to 2 minutes until the mixture starts to thicken.
04 -
Gently fold the thawed whipped topping into the pudding mixture until fully combined.
05 -
Using an offset spatula, spread half of the pudding mixture evenly over the graham cracker base.
06 -
Place another layer of graham crackers over the pudding layer.
07 -
Spread the remaining pudding mixture evenly over the second graham cracker layer.
08 -
Add the last layer of graham crackers on top of the pudding.
09 -
Microwave the lemon frosting for 45 seconds to soften. Stir well, pour over the final graham cracker layer, and use an offset spatula to spread evenly.
10 -
Refrigerate for 8 hours or overnight to set.
11 -
Cut into 3 by 4 slices using a sharp knife. Garnish each slice with one lemon slice and 1 to 2 fresh mint leaves if desired.