Mix together flank steak, lemongrass, basil, garlic, fish sauce, and black pepper.
Allow to marinate for 30 mins or longer.
Heat pan on med high with canola oil.
Stir-fry beef very quickly until desired done-ness, don't over cook it. It only takes a couple of minutes!
Split baguette and butter the top and bottom.
Build your banh mi.
Cucumber, beef, fried shallot, pickled daikon and carrot, chilli, and cilantro.