Prepare the Meatballs (Getting Started):

1. Combine Ingredients (The Mixing Bowl Magic): In a large mixing bowl, gently combine the ground turkey, breadcrumbs, egg, minced garlic, finely chopped onion, chopped parsley, dried oregano, ground cumin, salt, and pepper.
2. Mix Gently (The Key to Tenderness): Mix the ingredients until they are just combined. Avoid over-mixing the meatball mixture. Over-mixing can develop the gluten in the breadcrumbs, resulting in tough, dense meatballs.
3. Shape Meatballs (The Rolling Process): Using your hands, gently roll the mixture into small meatballs, about 1 to 1.5 inches in diameter. Try to make the meatballs uniform in size so they cook evenly. This should yield approximately 16-20 meatballs.

Cook the Meatballs (Choose Your Adventure):

1. Oven-Baked Option (Hands-Off Cooking): Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper for easy cleanup. Place the meatballs on the prepared baking sheet, ensuring they are not overcrowded. Bake for 15-20 minutes, or until the meatballs are fully cooked through and golden brown. Use a meat thermometer to check the internal temperature of the meatballs. They should register 165°F (74°C) to ensure they are cooked safely.
2. Pan-Fried Option (Searing for Flavor): Heat a large skillet over medium heat. Add a small amount of olive oil to the skillet. Once the oil is hot, add the meatballs to the skillet in batches, being careful not to overcrowd the pan. Cook the meatballs for 4-5 minutes on each side, turning them occasionally, until they are golden brown and cooked through. The searing process creates a delicious crust on the meatballs.
3. Air Fryer Option (Quick and Crispy): Preheat your air fryer to 380°F (193°C). Place the meatballs in the air fryer basket in a single layer, ensuring they are not overcrowded. Overcrowding can prevent the meatballs from cooking evenly. Cook for 10-12 minutes, flipping them halfway through, until they are cooked through and have a nice crispy exterior.

Make the Tzatziki Sauce (The Cool and Creamy Companion):

1. Grate and Drain Cucumber (The Moisture Control): Grate the cucumber using a box grater. Then, wrap the grated cucumber in a clean kitchen towel, paper towel, or cheesecloth and squeeze out as much excess moisture as possible. This is a crucial step! If you don’t drain the cucumber properly, your tzatziki sauce will be watery and thin.
2. Combine Ingredients (The Flavor Fusion): In a medium-sized bowl, combine the Greek yogurt, grated and drained cucumber, minced garlic, freshly squeezed lemon juice, chopped fresh dill, and olive oil.
3. Season and Chill (The Flavor Development): Stir the ingredients well to combine. Season with salt and pepper to taste. Don’t be afraid to taste the sauce and adjust the seasonings as needed. Cover the bowl and let the tzatziki sauce chill in the refrigerator for at least 30 minutes before serving. Chilling the sauce allows the flavors to meld together and intensifies the taste. It also helps the sauce to thicken slightly.
4. Serve (The Presentation): Serve the warm turkey meatballs with a generous dollop of the chilled tzatziki sauce on the side. The contrast between the warm, savory meatballs and the cool, refreshing tzatziki is simply divine.