Boil and peel eggs and set aside.
Heat oil in a pan.
Add garlic and onions and sauté until fragrant. About 1 minute.
Add bell peppers and mushroom and sauté for 2-3 minutes or until soft.
Add soy sauce and vinegar and add salt if necessary. If you are using ketchup, add it. Sauté for 2 more minutes.
Add eggs, stir and remove from heat.