In a bowl put all the marinade ingredients rosemary, salt, ginger, garlic, soy sauce, vinegar and oil. mix and set a side.

Put beef in the marinade and coat well. Let it sit for 30 min.

Put or brush oil in your skillet on medium high heat. Place beef slice on let them cook on one side then flip to cook the other side

Serve hot with ugali and greens Or rice and vegetables.