01 - In a large mixing bowl, combine the ground beef, chopped onion, minced garlic, breadcrumbs, egg, parsley, mint, oregano, cumin, lemon zest, salt, and pepper. Mix gently until just incorporated — avoid overworking the meat to keep the meatballs tender.
02 - With lightly moistened hands, roll the mixture into walnut-sized balls, yielding approximately 20 meatballs. Arrange them on a tray as you work.
03 - Heat olive oil in a large nonstick skillet over medium heat. Working in batches to avoid crowding, fry the meatballs for 8–10 minutes, turning occasionally, until deeply browned on all sides and cooked through to an internal temperature of 160°F. Transfer to a paper towel–lined plate to drain.
04 - While the meatballs cook, stir together the Greek yogurt, lemon juice, chopped dill, minced garlic, and salt and pepper to taste in a small bowl. Adjust seasoning as desired.
05 - Arrange the hot meatballs on a platter with the yogurt sauce alongside for dipping. Garnish with additional fresh parsley if desired. Pair with warm pita bread, a Greek salad, or rice pilaf.