A balsamic reduction is the super secret weapon you have in your arsenal when you're wanting to impress people at a dinner. It's the most delicious, one ingredient, magical spell you can cast on the most boring of dishes.
Pour your vinegar in a cold pot and turn it up to med-high heat.
You want it to simmer, not really boil. If you put the heat up too high and let it sit there to reduce then.. well.. bad things happen.
Let it simmer for about 10 minutes. The vapors will be filling the air in the shape of skulls and bones, the vinegar will be dancing the dance of its people and it'll reduce away. You'll notice by not only seeing where the top of the vinegar sits in the pan (if you saw where it was when you first put it in), or you can tell by the coat it leaves on a spoon or maybe even the bottom of the pan when you tilt it over.
It's a hot liquid right now so you can't tell exactly how syrup-like it is. But pour it in a container and put it aside for a bit and you'll see the fruit of your labors soon. I put mine in the fridge for a few and it's fine.
Salad
Slice your tomato and mozzarella in uniform slices. This is ideal for presentation, so if you're just going to be shoving this in your face then don't worry about being uniform.
Now, Season. Next to the reduction, seasoning the tomato and cheese is probably the next most important part of the dish.
Sprinkle the salt, grind the pepper, and try not to eat anything yet. Don't forget to flip all the slices over and give that side some love too.
At this point, depending on the condition of your reduction, you should be ready to plate. Preferably you want to wait until it's cool. So hopefully you planned in advance.
Go ahead and get a small bed of mixed greens on a plate. On top of that, put a tomato, then some cheese, and a basil leaf. Repeat in the same order till the tower is 6 high - 3 tomato and 3 cheese.
Now drizzle some oil. Then drizzle some balsamic reduction... And you're done!
Notes
One good sized tomato and one good sized ball of mozzarella is enough for the wife and I to both have 3 slices of each. Typically, that's the serving for the salad.
You can find fresh mozzarella in the specialty cheese case at your supermarkets deli/produce area. Again, I buy mine in a 3 pack at BJ's for $8.
I used a small handful of mixed greens on the bottom of the salad.
Rule of thumb: Reducing your amount of vinegar by half is good enough for a syrup consistency. You can go more, and it'll be thicker and even sweeter, so it's up to you, but by half works well for starting at 1 cup.
Basil is optional, but please include it. It's the DJ's bumpin' base to the party that's going on in your mouth.
And for the love of all that is holy, whatever you do, don't stick your face in the vapors of the evaporating vinegar. I know, that's like saying "don't look down!" but at least now you can never say I didn't warn you.