Add all of the ingredients, except the vanilla extract to a medium saucepan. Simmer on low heat for 20-30 minutes or until thickened and reduced by almost half.
Mine took exactly 28 minutes. Be sure to stir often and don't walk away from it. The mixture will thicken further as it cools.
Remove from the heat and whisk in the vanilla extract . Allow to come to room temperature, then store in the fridge for 5-7 days. When you are ready to use it in a recipe that calls for Sweetened Condensed Milk, pop in the microwave for 6-8 seconds and it will loosen up perfectly! Or add a tiny bit of hot water and stir!