Pork belly cooked in a bag

I am continuing to try ways of cooking whole pieces of meat for cold platters and sandwiches. This version was especially good: soft, tender and full of spice flavor, even through the skin. Once chilled, it slices thinly without falling apart.
Adjust servings in the full version
Wash the brisket. Dry with paper towels. If the skin is poorly processed, then scrape it well with a knife and rinse with running water. I had a clean, good piece, so no additional manipulation was required.
You can use the spices you like. I chose paprika: regular and smoked (by the way, I highly recommend it if you are not yet familiar with this spice), ground red pepper and a barbecue mixture.
Rub a piece of meat thoroughly on all sides with spices. They stick to the meat very well and do not crumble.
Now, perhaps, the most difficult and crucial moment. You need to wrap the meat in cling film so that there is no air left inside.
To prevent water from getting inside, wrap it in another layer of film. Please note that the film must be labeled “food grade”.
If you have time, put the meat in the refrigerator to marinate. If not, move on to the next step.
Boil water in the multicooker bowl. Look at the volume for yourself: the meat should be completely hidden by water.
Place the brisket wrapped in film into boiling water. Let's boil. And let it simmer for 20 minutes. After this, switch the multicooker to the “Warming” mode and leave the meat to simmer for 12 hours.
I set my multi-cooker at 80°C in the “Multi-cook” mode for 12 hours.
Keep the meat submerged. If trapped air makes it float, weigh it down. I sometimes use part of a springform cake pan; the photo shows the same method with another dish.
After 12 hours, remove the meat from the water. Without removing the film, let it cool. Then put it in the refrigerator until completely cool. This is a photo of the already cooled brisket.