• Add 1 cup balsamic vinegar to a saucepan. The wider your saucepan, the faster it will reduce.
• Turn the heat to medium. Stir occasionally until the mixture starts to lightly bubble from the center, then adjust the heat to maintain a very low simmer. Continue stirring occasionally for about 15-25 minutes, or until the mixture has reduced by half.
• How long it takes depends on how powerful your burner is, how high you set the heat, and how wide your pan is.
• You can continue reducing the balsamic until it reaches about 1/3 of the original volume (rather than half), but don't go more than that. For example, for this photo shoot I simmered 3 cups of balsamic vinegar until I had about 1 cup of reduction. You will know the reduction is done when it has a syrupy, glaze-like consistency and coats the back of a spoon. Keep in mind that it will continue to thicken a bit as it cools.
• Remove from heat and let cool slightly. Transfer to a mason jar with lid or other container with a lid and let cool completely. Store in the fridge. Balsamic reduction lasts in the fridge for several months! Tuck it in the door of your fridge and pull it out whenever you want to add a little something special to your meal!

Optional variation:

• Add sweetener to your balsamic vinegar if you are using it for dessert. Add up to 6 tablespoons of sweetener of your choice (or less) for every 1 cup of balsamic vinegar you are reducing. (For example, if you are reducing 3 cups of vinegar, that would be 18 tablespoons sweetener, which is 1 cup + 2 tablespoons.) You can use sugar, brown sugar, honey, maple syrup, etc.
• Stir in the sweetener at the beginning and make sure you stir until any granules are dissolved. Then continue with the recipe as described.