In a saucepan over medium heat, add vanilla, water, brown sugar, and white sugar, and bring to a simmer while stirring until sugars dissolve.

Add cinnamon and cook for 3 more minutes or until the mixture thickens.

Then remove from heat and leave to cool for 20 minutes.

Use the syrup immediately or transfer it to an air-tight container and place it in the refrigerator for up to 1 month.