In a small saucepan over medium-high heat, stir together brown sugar and water. Toss in cinnamon stick.
Bring to a boil and allow to boil for a minute until the sugar is completely dissolved. Remove from heat and allow cinnamon stick to steep in the syrup about 10 - 15 minutes. Stir in vanilla extract.
Pour into a mason jar or container with an airtight lid and store in refrigerator.