Add the brown sugar, water, and a pinch of salt to a small pot. Heat over medium low, stirring occasionally, until the sugar has fully dissolved.
Increase the heat slightly to medium and bring the mixture to a simmer. Simmer for 10-15 minutes until slightly reduced and thickened.
Remove from heat and stir in the vanilla extract and cinnamon. The syrup will thicken as it cools.
Allow the syrup to cool, then transfer to a jar or air tight container with a lid.
Enjoy! Tip: Make sure to shake or stir the syrup before adding to your coffee. The cinnamon will settle slightly at the bottom.