Score the rind on the belly in a grid shape. Rub with salt and pepper. Heat some oil in a saucepan. Place the meat with the rind side down. Fry in a preheated oven at 160 degrees. Pour hot stock every 10 minutes. After 30 minutes, remove the meat and place the vegetables, except for 1/4 of the garlic, in the roaster. Place the belly on it with the rind facing up. Let simmer for 10 minutes. Take the meat out again.
Toast the vegetables with tomato paste and caraway seeds. Sprinkle some sugar on top. Let it caramelize. Deglaze with white wine. Pour in the remaining stock. Place the meat on top with the rind facing up. Let simmer for another 90 minutes. Pour the dark beer several times over the last 20 minutes. That makes the rind nice and crispy.
For the seasoning paste, crush the 1/4 clove of garlic and mix with the butter, parsley, rosemary, zest and caraway seeds. Refrigerate.
Remove the meat and vegetables from the roaster. Keep warm. Reduce the sauce a little if necessary. Thicken with the seasoned butter before serving and season to taste.
Arrange the fried vegetables on a plate. Cut the meat into slices and serve on top. Napkin with the sauce and serve e.g. napkin dumplings.