1. Add the orange gelatin powder to a large mixing bowl. Pour in the boiling water and whisk until fully dissolved, about 2 minutes.
2. Pour in the ice cold water and whisk until the mixture is frothy.
3. Gradually fold in the thawed whipped topping and whisk until smooth and creamy, achieving a light orange color.
4. Chill the mixture in the refrigerator for about 30 minutes or until it thickens enough to spoon into the pie crust.
5. Spoon the gelatin mixture into the graham cracker crust and smooth evenly with a spatula.
6. Refrigerate the pie for 4 hours or overnight to allow it to fully set.
7. For an optional topping, whip heavy cream, powdered sugar, and vanilla in a large bowl until stiff peaks form. Dollop or pipe over the pie and garnish with orange zest if desired.