In a small sauce pan stir sugar, salt, cocoa and cornstarch together. Add water and turn heat to medium and stir ingredients until combined with a whisk.

Stir until mixture thickens slightly and starts to gently simmer. Add vanilla and butter or coconut oil and stir until melted.

Turn off the heat, add chocolate chips and stir until it is completely melted.

Let cool then transfer to a jar or container. Store in the refrigerator, the chocolate sauce will thicken as it cools.