Remove steak from packaging and set aside 10 minutes. Once steak reaches room temperature, place steak in deep plate or storage container. In small bowl, combine hoisin sauce, soy sauce, honey, fish sauce, garlic, 1 teaspoon rice vinegar and five-spice powder; pour over steak. Cover and marinate in fridge at least 2 hours, or overnight.

In small pot over medium heat, heat remaining rice vinegar, sugar and salt. Cook and stir until sugar and salt dissolve. Remove from heat and let cool.

Place carrots in deep plate or storage container. Pour cooled pickling liquid over carrots. Set aside to marinate.

Remove steak from marinade and pat dry. Reserve marinade.

Heat oven to 325 F.

Heat heavy-bottomed pan over high heat and add oil. Once oil begins to smoke, add steak. Sear both sides, about 1 minute per side. Lower heat to medium.

Add reserved marinade and water to pan. Cook, covered, 3 minutes, removing lid to flip meat occasionally. Remove lid and let sauce reduce 1 minute, or until slightly thickened.

Transfer steak and sauce to large plate and let rest 10 minutes before slicing.

Toast baguettes in oven 5 minutes. Let cool 5-10 minutes.

Slice baguettes along middle without cutting through.

Slice steak into thin pieces.

Spread mayonnaise on baguettes and add 1-2 lettuce leaves to each. Layer steak on lettuce leaves followed by cilantro, cucumbers and pickled carrots. Slice baguette into two sandwiches.