Place milk, 1 cup of cream, sugar, salt, and mint in a medium sauce pan. Heat until the mixture is steaming, but not boiling. Remove from heat and cover for 1 hour to let the leaves steep in the milk.
Once leaves have steeped for 1 hour, strain mixture to remove the leaves. Push the leaves against the strainer to extract all the color and flavor from the leaves. Place back in saucepan and heat back up so it's steaming again. Remove from heat.
Add yolks to a medium bowl and very slowly whisk in warm milk. Transfer mixture back to saucepan and set over medium heat. Stir constantly until mixture begins to thicken and is 170 degrees. Mixture should coat the back of the spatula. Remove from heat immediately so the mixture doesn't scramble.
Place remaining heavy cream in a large bowl and place strainer over bowl. Pour thickened yolk mixture through strainer to remove lumps. Stir with cream. Add vanilla extract and food coloring. I only needed 4 drops of food coloring, but feel free to add more or less to get the desired color.
Chill mixture until completely cold, about 4-6 hours. Once chilled, ice cream base is ready for your machine. Freeze ice cream according to machine instructions.
Once mixture is ready, layer ice cream with Oreos and hot fudge. I did two layers to make sure every bite had tons to cookie and fudge. Freeze ice cream until solid, about 8 hours.