Combine 2 tablespoons of the coconut milk with the arrowroot in a small bowl and set aside.
In a medium-sized saucepan over medium-high heat, bring the remaining coconut milk and honey to an active simmer, about 4 minutes.
Whisk in the arrowroot mixture, carob, and salt and stir until thick, another minute or so.
Let cool to room temperature, then refrigerate until cold, at least 30 minutes.
Run through your ice cream maker according to the manufacturer's instructions, adding the marshmallows and almonds as instructed.