It is necessary to tie the roast beef to hold the meat together. Most of the time, this is done in advance when you buy the meat, but if this is not the case, you need to do it yourself.

Then season the meat with salt and pepper and vacuum pack it.

Then cook the meat for 7 hours at 55 degrees Celsius (131 degrees Fahrenheit) in the water bath. If you are unsure about the quality of your roast beef, give it 8 hours.

Take the meat out of the water bath.

Remove the meat from the bag and pat it dry with a clean tea towel.

Heat a pan with ghee or equal parts butter and oil, and give the meat a nice crust all around. Alternatively, you can sear the meat on your grill. Make sure the grill is as hot as possible and sear the meat on the hot grill. As a third alternative, you can use a blowtorch to sear the meat. Regardless of which method you choose, the meat should have about 30 seconds on each side.

Finally, remove the twine from the meat and cut the roast beef into thin slices.