Mix the cocoa, sugar and water in a sauce pan on the stove at a medium high heat, whisking constantly.

Heat until boiling and then boil for 1 minute more. Still, whisking constantly.

Remove from heat and slightly cool.

At this point you can add a pinch of sea salt, if you'd like

Next, add vanilla extract and cool completely

Store in a covered glass jar in the fridge.

Syrup will thicken as it cools.