Set your Anova Precision Cooker to 131ºF/55ºC.
Liberally season both sides of your flank steak with salt, pepper, and garlic powder.
Place in zip-locking bag and release as much air as possible from the bag.
Place into the heated bath and set timer for 90 minutes.
Remove from bath and pat dry with paper towel or kitchen cloth.
Sear as desired. We used a cast-iron pan brushed with 1 Tablespoon of avocado oil.
Slice steak very thinly against the grain.
Mix marinade in a medium-sized bowl by combining lime juice, fish sauce, chopped chilies, minced lemongrass, minced garlic, and sugar.
Add beef and stir to coat. Set aside to marinate.
Lay 5 or 6 Romaine leaves on your serving plate as a base. Finely chop the remainder and place on top of whole leaves in a wide pile.
Sprinkle julienned pepper, carrot, and tomato around the outer edges of the lettuce.
Mix the shallot, cilantro, and mint through the marinated beef.
Using your hands or a large spoon, pile the steak on top of the lettuce.
Dig in!
