In a large bowl, combine the ground beef, chopped onion, minced garlic, chopped parsley, cumin, coriander, paprika, cayenne pepper, salt, and black pepper. Mix gently with your hands until all ingredients are well combined, but do not overmix.
Divide the mixture into 8 equal portions. Shape each portion around a skewer to form a kebab. If using wooden skewers, soak them in water for at least 30 minutes before use to prevent burning.
Preheat your grill to medium-high heat or preheat your oven to 400°F (200°C).
Grill the kebabs for 6-8 minutes per side, or until cooked through and nicely browned. If baking, place the kebabs on a baking sheet lined with parchment paper and bake for 15-20 minutes, turning halfway through.
While the kebabs are cooking, prepare the tzatziki sauce. In a small bowl, combine the Greek yogurt, grated cucumber, minced garlic, chopped dill, lemon juice, and salt. Stir until well mixed.
Serve the Beef Kofta Kebabs hot with the tzatziki sauce on the side. They are also great served with pita bread, rice, or a fresh salad.
Notes
For a spicier kick, increase the cayenne pepper. Ensure the onion and garlic are finely minced for better integration into the kofta mixture.