01 - In a large bowl, combine ground lamb, grated onion, garlic, parsley, mint, cumin, coriander, cinnamon, smoked paprika, chili flakes, salt, black pepper, egg, and breadcrumbs. Mix gently until just combined, avoiding overmixing.
02 - With damp hands, shape the mixture into walnut-sized balls, forming about 20 meatballs.
03 - Heat olive oil in a large skillet over medium heat. Fry meatballs in batches, turning regularly to brown all sides for 6 to 8 minutes, or until fully cooked through. Drain on paper towels.
04 - In a small bowl, whisk together Greek yogurt, lemon juice, chopped mint, ground cumin, salt, and pepper. Chill until ready to serve.
05 - Serve the warm meatballs accompanied by the chilled yogurt sauce.