Preheat your oven to 400°F.
In a large bowl, combine the ground turkey, breadcrumbs, Parmesan cheese, parsley, onion, garlic, oregano, salt, pepper, and egg. Mix until well combined.
Form the mixture into meatballs, about 1.5 inches in diameter, and place them on a baking sheet lined with parchment paper.
Drizzle the olive oil over the meatballs and bake for 20-25 minutes, or until they are cooked through and golden brown.
While the meatballs are baking, prepare the tzatziki sauce. In a medium bowl, mix together the Greek yogurt, grated cucumber, garlic, lemon juice, dill, salt, and pepper. Adjust seasoning to taste.
Once the meatballs are done, serve them warm with the tzatziki sauce on the side.