Turn on your broiler. Place the oven rack on the top-most level.
Combine the beef, onion, garlic, parsley, coriander, cumin, salt and pepper together in a large bowl.
Divide the mixture into 12 roughly even balls. Take one wood skewer and mold one ball around the top-end of the skewer. Shape it into a flat oval. Repeat for the remaining 11 skewers.
Place a rack on a broiler pan. Spread an even coat of vegetable oil over the rack to prevent the meat from stick. Place the skewers on top of the rack. Put the pan into the broiler for 3 minutes. Flip the skewers and cook for another 3 minutes or until done.
To serve, place on a platter and serve with pita bread and tzatziki sauce.