Marinate the Angus Beef Steak in salt, pepper, and vinegar for a few hours.
Grill or pan-sear the steak with butter on low to medium flame until it is cooked to your liking.
Set the steak aside to cool and cut it into small chunks.
Scoop out the avocado and put it into a blender.
Squeeze out the lime juice and add it to the avocado.
Blend the avocado and lime juice into a smooth paste.
Separate the leaves of the Romaine lettuce.
Spread the lime and avocado puree on the romaine lettuce leaves, place a few chunks of the steak on each leaf, and wrap them into rolls.
Serve and enjoy at room temperature.