Rinse your cabbage to remove soil or similar.

Cut it lengthwise and then cut it again lengthwise so you have 2 quarters. I usually say 1 quarter per person.

Season the cabbage with salt and pepper and put it in a bag. Pour buttermilk until it is covered.

Let it marinate for a couple of hours, I suggest a minimum of 2 hours and preferably up to 4-6 hours. If you don't have buttermilk, you can still make the dish without marinating beforehand, but you will need to add butter, oil, or another fat to your vacuum bag.

Rinse the cabbage under a cold tap and pat it dry with a clean tea towel.

Season with salt and pepper and vacuum pack it.

Cook it for 30 minutes at 85 degrees Celsius (185 degrees Fahrenheit),

Carefully remove the cabbage from the vacuum bag and dry it thoroughly.

Fry the cabbage on very high heat, either on a grill, griddle, or pan on all 3 sides. Give it a bit more time on the outer side until it almost gets burnt - you can always remove the outer leaf.