Season the meat with salt and pepper, cumin, oregano, and cut it in cubed pieces.
Heat a skillet with ¼ cup of the sunflower oil and let it brown the pork cubes for a few minutes, then add the wine, lower the heat and simmer for 5 minutes. Set aside.
Sauté over medium heat onions, garlic, carrots and parsnips for about 4-5 minutes with the other ¼ cup of oil.
Then add ½ cup water to the pan and cook for about 10 minutes. Chop tomatoes and add them to the pan for 5 minutes to slowly simmer until liquid evaporates.
Transfer the content from the pan to clay pot and add leeks.
Preheat the oven to 250 degree.
Cover the clay pot with its lid and place in oven. Bake it for 3 hours.
If you do not want to use the oven, you can make it in a crock pot instead.
Serve hot with bread.