Filipino Beef Steak or Bistek

1/2 kilo of beef (round, sirloin or tenderloin), sliced 1/4-inch thick
4 tbsp. of kalamansi (native lemon) juice
1/4 c. of dark soy sauce
freshly-ground pepper
1 tsp. of minced garlic
2 large onions, cut into rings
2 tbsp. of cooking oil

Heat a heavy skillet. Add oil. Lightly fry the onion rings. Remove from skillet and drain on paper towels. Keep warm.

Reheat oil until smoking. Pan-fry the beef slices in batches, removing them as they brown. When all the beef has been cooked, pour the marinade into the skillet and boil for 1 minute. Arrange beef slices on a plate. Place the onion rings on top. Pour the sauce over the onions and beef. Serve at once.