Coat frying pan with olive oil and balsamic vinegar and begin heating on medium heat.
Add in diced onion and begin cooking until caramelized.
While onions begin to caramelize, whisk eggs in separate bowl until evenly mixed, adding in shredded cheese, salt, and pepper to taste.
Once onions are caramelized, pour in egg mixture.
Continue cooking and scrambling over medium heat to desired consistency.
Serve with toast or biscuits.