Use a food processor OR place the cracker sheets into a large, clear food storage bag and use the back of a spoon to crush them into tiny crumbs.
Pour the crumbs into a large bowl and mix in the sugar.
Add the melted butter and mix with a fork until well-combined.
Put the crumbs into the 10” pie pan and press firmly into the bottom of the pan and up the sides, smoothing the edges when bottom and sides are covered.
Set aside.
Pie Filling
Combine ice cream, pumpkin, brown sugar, cinnamon, sea salt, and nutmeg in a large mixing bowl and place in freezer.
Stir the freezer mixture with a large spoon every ten minutes until it begins to stiffen, about 30 minutes.
Remove pumpkin mixture from freezer and scoop it evenly into the graham cracker crust.
Cover and place into freezer for two hours.
Remove and serve with whipped topping and/or optional garnishes before it melts.