In a large bowl, combine ground beef, onion, garlic, parsley, cumin, coriander, salt, and pepper. Mix until well combined but do not overmix.

Shape the mixture into equal portions (4-6) and mold onto skewers into oval shapes.

Preheat the grill to medium-high heat (375°F). Soak wooden skewers in water if using.

Grill the kebabs for 10-12 minutes, turning occasionally until browned and cooked through (internal temperature should reach at least 160°F).

Serve hot with warm pita bread and tzatziki sauce.