Pork Kebab in Kefir Marinade

Cut the pork shoulder (1800 g) into large cubes, and lightly crush the onion (360 g) with your hands. Mix the 4% kefir (500 g) with the onion (360 g), salt (12 g), and black pepper (2 g), then add the pork shoulder (1800 g) to the marinade and leave it in the refrigerator for at least 2 hours, or preferably 4 hours.

Thread the meat onto skewers or arrange it on a rack and cook for about 18-20 minutes until fully done, turning from time to time. Serve the kebab hot right after cooking.