Place vegan chocolate bar into a medium glass mixing bowl; set aside.
Sprinkle gelatin over 1 tbs cold water in a small dish; set aside.
Combine nut milk, coconut sugar + cacao in a small saucepan over medium heat. Whisk until cacao is dissolved + mixture comes to a simmer.
Remove from heat, pour over chocolate.
Let it stand for 1-2 minutes, then whisk until chocolate is melted. Whisk in vanilla and the gelatin mixture.
Portion the mixture evenly among 2 ice block molds and place in the freezer. Freeze for at least 4 hours or overnight.