Form patties: Divide the meat into 4 equal parts and shape them into 4 patties. Don’t overcompress the meat and gently form them into disks. Make them slightly wider than your buns as they will shrink a little bit during cooking.
Chill them for at least 20 minutes before sous vide cooking.
Sous vide cook patties: Fill a large container or pot with water. Attach the sous vide precision cooker and set the temperature to 135°F (57°C)*.
Sprinkle both sides of the chilled burgers with salt and pepper.
Place the seasoned patties to a large zip-lock bag and arrange in a single layer. Seal the bags using the “water displacement” technique: seal all but one corner of the bag, and slowly place it in the water bath. Make sure everything below the zip-line is covered by water. Then seal the rest of the bag. (Don’t use a vacuum sealer as it will overcompress the meat.)
Leave the bags in the warm water bath and cook for 40 minutes (or up to 2 hours). Make sure the meat is fully submerged while the seams of the bag are above water. You can add heavy kitchen items to weigh the bag down if necessary.
While the patties are cooking, prepare the condiments, toppings, and toast buns.
When the timer goes off, carefully remove the patties from the bag. Let them rest for about 10 minutes at room temperature and pat dry with paper towels. Then season with more salt and pepper.
Sear the patties: Heat the grill on high heat. When it gets smoking hot, add the patties and cook for about 1 minutes until well browned. Flip the patties and add cheese to the top surface. Cook for 45 seconds to 1 minute until the cheese is half-melted. (You can also use a skillet, but make sure to add a tablespoon of oil before searing).
Assemble the hamburger with the cooked patties, toppings and condiments as desired. Serve immediately.