01 - Wrap the grated cucumber in a clean kitchen towel and squeeze firmly to remove excess moisture. In a mixing bowl, combine the Greek yogurt, drained cucumber, minced garlic, dill, lemon juice, olive oil, and season with salt and pepper. Stir until smooth and well blended. Cover and refrigerate until ready to serve for the best flavor.
02 - In a large mixing bowl, combine the ground turkey, breadcrumbs, egg, minced garlic, grated onion, parsley, mint, oregano, cumin, salt, and pepper. Gently mix with your hands until just combined, being careful not to overwork the mixture.
03 - Using your hands, roll the mixture into 18 to 20 uniform walnut-sized meatballs. Place them on a plate or tray as you work.
04 - Heat olive oil in a large nonstick skillet over medium heat. Add meatballs in batches to avoid overcrowding. Cook for 8 to 10 minutes, turning regularly, until golden brown on all sides and cooked through to an internal temperature of 165°F.
05 - Preheat oven to 400°F. Arrange the meatballs on a parchment-lined baking sheet and brush or spray lightly with olive oil. Bake for 15 to 18 minutes, turning halfway through, until golden brown and cooked through to an internal temperature of 165°F.
06 - Arrange the cooked meatballs on a serving platter with a generous dollop of tzatziki sauce. Garnish with fresh herbs and serve alongside lemon wedges. Accompany with warm pita bread or a crisp side salad if desired.