Pulse graham crackers and brown sugar in a food processor until fine crumbs. Melt the butter and mix it into the crumbs. Press this mixture into a greased pie dish and freeze for 15-20 minutes.

Whisk together cold milk, green food coloring, and mint extract in a mixing bowl. Gradually add pudding mix and whisk for 2-3 minutes until thickened. Let it sit for 5 minutes.

Gently fold in thawed whipped topping into the mint filling mixture until combined.

Spoon the mint filling into the chilled crust, smooth the top, cover with plastic wrap, and freeze for at least 6 hours or overnight.

Allow the pie to sit at room temperature for 5-10 minutes before slicing to ensure cleaner cuts.