Combine the milk, whipped topping and instant pudding mix.
Arrange a layer of graham crackers in a 13 x 9-inch baking dish without overlapping.
Now spread have the instant pudding mixture on top.
Add another graham cracker layer.
Add the rest of the pudding mix on top.
Add the last layer of graham crackers.
Freeze for 30 minutes.
Bring the frosting to room temperature (if refrigerated) and spread across the top of the cake, ensuring you cover the edges.
Cover and chill in the refrigerator for 4 hours, then serve.