How to Make a Balsamic Reduction
To make a balsamic reduction, choose a high-quality balsamic vinegar that is flavorful and sweet. Pour your balsamic vinegar into a wide, shallow pan and bring it to a boil over medium heat. If you want a sweet reduction to pour over fruit, you can add sugar as you're heating the vinegar, or you can add it at the end if you prefer. Once the vinegar reaches a boil, turn the heat to low and simmer the vinegar for 10-20 minutes. If you added sugar to your vinegar, stir it occasionally to keep it from sticking to the pan. Allow the reduction to cool completely before serving.
Select your balsamic vinegar. Choose a high-quality balsamic vinegar that's flavorful and sweet. Look for a balsamic vinegar of Modena which can have a great complex flavor (especially the more expensive it is). Balsamic vinegars of Modena reduce down well. Lighter balsamic vinegars are more tart while darker ones are usually sweeter. Avoid using a traditional balsamic vinegar (labeled "Aceto Balsamico Tradizionale" and stamped "D.O.P"). This vinegar will lose flavor when heated. Measure out your balsamic vinegar. You can make any increment of balsamic reduction you like. If you use a lot of balsamic reduction on a regular basis, consider starting out with a whole bottle of balsamic vinegar. A bottle is usually around 16 ounces (2 cups). Pour the balsamic vinegar into a small heavy saucepan. If you're only planning on using the balsamic reduction for one meal or dessert, consider starting with just 8 ounces (1 cup) of balsamic vinegar. Using a wide and shallow pan will help the balsamic vinegar cook down more evenly. Consider adding sugar. If you're planning on drizzling your balsamic reduction over berries, a dessert, or ice cream, you may want to stir in 1/2 cup of granulated sugar to the pan with the balsamic vinegar. As the mixture reduces, the sugars will caramelize a little and give a slightly sweet taste to your reduction. Some people recommend adding sugar or other flavors (like cinnamon, orange, fig, or fresh herbs) to an already finished reduction. That way, you could use a straight balsamic reduction for more things. Turn the burner on to medium heat. The goal with reducing the vinegar is to slowly allow moisture to evaporate so that the liquid is reduced by half or two-thirds. This will make the balsamic reduction thick and syrupy. Cooking the vinegar over medium heat may prevent the reduction from burning. At this point, you may want to turn on your kitchen fan since the balsamic vinegar will begin to evaporate as it reduces. Allow the vinegar to heat up until it reaches a boil. If you're heating the balsamic vinegar in a wide shallow saucepan, it will quickly begin bubbling from the center. If you're using a smaller deep saucepan, it may take longer for the vinegar to come to a boil. Stay close to your stovetop while the vinegar is heating. It will only take a few minutes to begin boiling. If you let the vinegar boil too long, it can burn. Turn the burner to low. Once you see that the vinegar is bubbling a lot, turn the heat down to low. The boiling will slow to a simmer. Make sure the mixture continues to simmer as it reduces. If you notice it stop, turn up the heat till it begins bubbling a little. Simmering is just below the boiling point, so the vinegar should still be slightly bubbling. Leave it to simmer for 10 to 20 minutes. The liquid will gradually evaporate so that only half or two-thirds of the vinegar remains. If you're having trouble gauging how much has evaporated, look at the side of your saucepan. You should see a line at the point where the vinegar originally was. Use this to gauge how much moisture has evaporated. If you added sugar to your vinegar, you can stir the mixture occasionally to keep it from sticking to the pan. If you'd like a thinner sauce for drizzling, cook it closer to 10 minutes. If you want a thicker sauce, cook it for closer to 20 minutes. Cool and store your balsamic reduction. Pour your reduction into a bowl and allow it to cool completely before serving. It will get slightly thicker as it cools. If you plan on drizzling the reduction, transfer it to a squeeze bottle or small pitcher. For longer storage, put the reduction in an air-tight bottle and refrigerate it for up to two weeks. Use the reduction as a sauce. Drizzle roasted vegetables with the reduction to add another complex flavor. Balsamic reduction also works well when drizzled over pizza or grilled salmon. You can also use the reduction as a dip. For example, try dipping a grilled cheese sandwich in your reduction. If you want to keep things simple, try drizzling the reduction over a fresh ripe avocado. You can also add a few teaspoons of the reduction to your pasta sauce to create a more unique flavor. Create salad dressings with the reduction. A traditional Caprese salad is one of the most well-known salads to use balsamic reduction as a dressing. This fresh mozzarella and tomato salad simply uses the reduction as a drizzled dressing. But you can also combine the reduction with other salad dressings to improve their flavor. Or you can make your own simple balsamic dressing by combining and shaking together these ingredients: Equal parts of your reduction and extra-virgin olive oil (try for 1/4 cup of each) 1/2 teaspoon grainy mustard 1/8 teaspoon sea salt a few grinds of fresh-ground black pepper Try flavoring desserts with the reduction. Strawberries are a popular fruit to pair with balsamic reductions. You can drizzle the reduction over fresh or roasted strawberries, peaches, or figs. For other sweet ideas, drizzle the reduction over vanilla ice cream. You can also drizzle cheesecake or berry pies with a little balsamic reduction. The reduction will cut some of the dessert's sweetness. 
Select your balsamic vinegar. Measure out your balsamic vinegar. Consider adding sugar. Turn the burner on to medium heat. Allow the vinegar to heat up until it reaches a boil. Turn the burner to low. Leave it to simmer for 10 to 20 minutes. Cool and store your balsamic reduction. Use the reduction as a sauce. Create salad dressings with the reduction. Try flavoring desserts with the reduction. 