In a medium saucepan, whisk together the cocoa powder, cane sugar, and salt. Break up any clumps in the cocoa powder to ensure a smooth syrup.
Slowly add the water to the dry ingredients while whisking continuously. This helps dissolve the sugar and cocoa powder, preventing lumps. Keep whisking until the mixture is fully combined and smooth.
Place the saucepan over medium heat and bring the mixture to a boil. Stir frequently to avoid burning or sticking. Once it reaches a boil, reduce the heat to a simmer.
Allow the syrup to simmer for about 5–10 minutes, stirring occasionally. The mixture will thicken slightly as it cooks. Don’t worry if it seems thin while hot— it will continue to thicken as it cools.
Remove the saucepan from heat and stir in the vanilla extract. Stir well to combine and enhance the flavor.
Let the syrup cool to room temperature in the saucepan. Once cooled, transfer it to a clean jar or container with a lid.
