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 to allow the flavors to meld while preparing the meatballs.
02 - In a large mixing bowl, combine the ground turkey, breadcrumbs, egg, minced garlic, grated onion, parsley, mint, oregano, cumin, salt, and pepper. Gently fold the mixture with your hands until evenly combined, being careful not to overwork the meat.
03 - Portion the mixture into 18 to 20 uniform walnut-sized balls, rolling each gently between your palms. Arrange on a plate or tray and set aside.
04 - Heat the olive oil in a large nonstick skillet over medium heat. Working in batches to avoid crowding, add the meatballs and cook for 8 to 10 minutes, turning every couple of minutes, until deeply golden brown on all sides and cooked through to an internal temperature of 165°F.
05 - Preheat the 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 and fully cooked.
06 - Arrange the cooked meatballs on a serving platter with a generous dollop of tzatziki sauce alongside. Garnish with fresh herbs and lemon wedges. Serve immediately with warm pita bread or a crisp side salad if desired.