Marinate the Steak: In a small bowl, add balsamic vinegar, honey, soy sauce, minced garlic, black pepper, and olive oil. Mix well.
Add flank steak to a zip-top bag, and pour the marinade into the bag.
Coat the meat thoroughly and vacuum seal the bag using “water displacement” technique: seal all but one corner of the bag, and slowly place it into a container with cold water. Make sure everything below the zip-line is covered by water. Then seal the rest of the bag.
Let it marinate for 2 hours in the refrigerator.
Sous Vide the Steak: Add water to the sous vide container or a large pot, set the Sous Vide Precision Cooker to 135°F (57°C) for medium rare doneness. This is my recommended doneness, and if you’d like to cook it more or less, follow the temperature guide in the post above.
When the steak is ready, place the vacuum-sealed bag in the water bath. Make sure the meat is completely submerged.
Cook for 2 hours.
When the timer goes off, remove the bag from the water bath.
Sear: Wipe off any extra moisture from the cooked steak with paper towel.
Place the skillet on medium-high heat and add olive oil. When the pan is very hot, add your steak and sear about 1 minute per side.
Slice your steak thinly against the grain and serve with your favorite sauce.