Ingredients:

½ beef, cut in thin square shape
½ cup of soysauce
¼ cup of calamansi juice or ¼ cup Lemon juice
3 glove of garlic minced 
1 onion, sliced into rings
½ cup oil
¼ teaspoon of sugar
¼ teaspoon of black pepper
½ cup water

Preparation:

In a medium-sized bowl, marinate beef slices in soy sauce, calamansi or lemon juice, minced garlic, ¼ teaspoon of black pepper, and onion for 10 to 20 minutes. Fry marinated beef slices in ½ cup of oil until brown. Do not throw the remaining marinate, set aside for later use. In the same frying pan, put together the fried beef slices, and the remaining marinate. Add ½ cup of water. Simmer for 10 to 15 minutes. Add ¼ teaspoon of sugar (optional) and wait for another 2 to 3 minutes. Best serve with rice.