First, pre-heat the oven to 400° F.
Wash the Brussels sprouts and cut the ends off and slice them in half either long or short ways.
Dice the five cloves of garlic.
Coat the bottom of an oven-proof medium to large pan with olive oil and heat on medium. When the oil gets hot, add the garlic and cook for a minute.
Add the Brussels sprouts so that they lay flat in the pan. Season them with salt and pepper and let them cook undisturbed for about five minutes or until they start to brown a little.
At this point, the oven should be heated to 400° F. Transfer the pan into the oven to cook for longer.
Every five to six minutes, check the Brussels sprouts and move them around a little bit. This will prevent them from burning in one spot.
In about ten to fifteen minutes, the Brussels sprouts should be tender and a little crispy. At this point, remove them from the oven and let cool for about two minutes.
Finally, stir in balsamic vinegar to your tasting, and if needed add a little bit more salt and pepper (I tend to like my food saltier than most).