In a pot, sauté the diced onion in oil until translucent. Trim the thick skin off the bacon and cut out any white cartilage, if present. Dice and add to the onion. Fry for about 7 minutes until it renders fat and browns lightly, stirring occasionally.
Cut the pork shoulder into 1 cm cubes. Add to the pot and fry for about 15 minutes, stirring occasionally. Meanwhile, season with salt and pepper.
Add the carrot, peeled and coarsely grated, and fry for 5 minutes. Add the garlic pressed through a garlic press and the paprika, and fry briefly. Add the Worcestershire and soy sauces, stir, and cook for about 1-2 minutes.
Pour in hot stock or water and bring to a boil. Cover and cook for about 45 minutes, until the meat is tender. If you used water, check whether the dish needs more salt.
Add the sliced napa cabbage and cover the pot. Cook briefly until the cabbage softens, then stir and continue cooking, covered, for about 10 minutes. If there's still a lot of liquid, reduce it by cooking uncovered. Finally, add the tomato paste and cook for about 2-3 minutes. Sift in the flour, stir, and bring to a boil. Sprinkle with chopped parsley.
