Using a wooden or silicone spoon, thoroughly mix the brown sugar, water, and vanilla essence in a small pot.
After bringing the ingredients to a boil, quickly reduce the heat to a simmer.
Simmer for ten to twelve minutes, stirring now and then. Note: Simmer for only 5 minutes if you're pressed for time, but a longer simmer time will result in a deeper flavor.
After taking the pan off of the stove, let it cool down before transferring it to an airtight container or mason jar for storing. Keep in mind that syrup will get thicker as it cools and will become even thicker after being refrigerated. If it looks "watery" immediately after finishing, don't worry—that's normal!
Make your favorite coffee, tea, hot chocolate, or any other hot or cold beverage that you would normally sweeten with sugar using this easy syrup.