In a medium bowl, mix together the crushed saltines and graham cracker crumbs. Pour in the melted butter and stir until the mixture resembles wet sand. Grease a 13x9-inch baking pan and press the crumb mixture into the bottom, then refrigerate for about 15 minutes to set.

In a large mixing bowl, whisk together the milk, instant chocolate pudding mix, and instant vanilla pudding mix. Whisk for about 2 minutes until thickened and lump-free.

Fold in the softened cookies and cream ice cream into the pudding mixture gently using a spatula, until well combined.

Spoon the ice cream and pudding mixture over the chilled crust, spreading evenly.

Add a layer of frozen whipped topping on top and smooth it out evenly. Sprinkle crushed Heath candy bars on top.

Cover tightly and freeze for at least 4 hours, or overnight if possible.

30 minutes before serving, remove from the freezer to let it sit at room temperature for easier slicing.