Sri Lanka Bistake Beef Steak Saute with Onion

Ingredients
BISTAKE
 * 450 gm Beef, Rump Steak
 * 2 Onion
 * 75 ml vinegar
 * 1 tsp salt
 * 1 tsp pepper, Black, coarse grind
 * 100 ml oil
 * 1 curry leaf sprigs
 * 2 cg cinnamon stick
 * 1 tsp mustard seed, ground
 * 100 ml Stock
 * 1 tsp Sugar
 * 1/2 tsp chile powder

Directions

 * 1) Slice the Beef into 50mm slices. Make Onion rings with 1 1/2 onions and chop remainder. Mix together the vinegar, salt and pepper in a bowl and marinate Beef for 1 hour.
 * 2) Heat the oil in a frying pan and when hot add the curry leaves, chopped Onion and cinnamon stick. When fragrant add the Beef and marinade. Cover pan and cook over a low heat until the Beef is tender. Remove the Beef and set aside.
 * 3) Add the Onion rings to the pan and stir fry for a couple of minutes. Add the mustard, stock, Sugar and chile powder and mix well. Put back the Beef slices and cook for a further 2-3 minutes. Remove the cinnamon stick before serving.