Combine the balsamic vinegar, water, onion, garlic and sugar in a saucepan and bring to a boil.

Remove from heat and let cool completely. This step is very important, as you don't want the balsamic mixture to cook the eggs.

Boil 6 eggs using your favorite method or just peel some already hard boiled eggs.

Put eggs in a large jar and pour cooled balsamic mixture over the eggs. Cover rtghtly and refrigerate for 5 days before serving.

After a day or two in the refrigerator, rotate the eggs a bit so that the sides touching the jar or other eggs will turn brown.