Mix soy sauce, sugar, lemon juice.
Use half of the mixture and marinate the beef. Add 1/2 of the garlic, and half of the onion. Mix until the meat is coated. Let sitĀ for at least 4 hours or overnight for best results.
Heat the cooking oil in a pan and fry the beef until it changes its color. Remove from the pan and set aside.
Using the same pan, saute' half of the sliced onion and garlic.
Add the beef back in the pan and add theĀ remaining marinade and water. Cover and let it cook for 20 more minutes, or until soft.
Add salt and pepper and season according to your liking.
Enjoy.