1 (12-ounce) Low Fat or FF Cool Whip (thawed)
1 (14-ounce) can sweetened condensed milk
3/4 cup key lime juice (found in the baking aisle)
1 prepared reduced fat graham cracker pie crust (I use Keebler)
Freshly grated lime zest, for sprinkling
In a bowl, gently fold together the Cool Whip, sweetened condensed milk, and lime juice until fluffy (DO NOT MIX HARD - YOU DO NOT WANT THE MIXTURE TO BE SOUPY - THIS WILL RESULT IN A FLAT PIE.) Spoon the mixture into graham cracker crust and smooth the surface with a spatula.
Freeze until firm, about 30 minutes. Sprinkle lime zest over the top before serving.