Preheat oven to 425 F.
In a large mixing bowl, mix pumpkin puree, pumpkin pie spice, salt, sweetened condensed milk, and eggs until smooth.
In a small bowl, mix activated charcoal and water until fully combined. Wear an apron as activated charcoal is messy!
Divide pumpkin pie batter into two bowls with equal amounts of batter in each.
Mix the activated charcoal slurry into one of the batter bowls until the batter turns uniformly black.
Pour a little bit of the orange batter into the center of the pie crust. The amount you pour will determine how thin or thick your stripes are. I did very little at a time, hence my very thin stripes.
Pour some of the black batter into the center of the orange batter.
Keep alternating colors until all of the batter is used.
Bake for 15 minutes.
Lower oven temperature to 350 F and continue to bake for for another 65 minutes or until the pie is just barely jiggly in the very center.
Cool to room temperature and then refrigerate at least four hours before slicing.