Preheat the oven. Set your oven to 400°F (200°C). Line a sheet pan with parchment paper and lightly mist with olive oil spray.
Mix the aromatics. In a large bowl, combine grated onion, garlic, parsley, dill, oregano, lemon zest, Greek yogurt, salt, pepper, and red pepper flakes.
Stir until well combined.
Add turkey and binders. Add the ground turkey, egg, breadcrumbs, and feta. Mix gently with a fork or your hands just until combined. Do not overmix or the meatballs can turn dense.
Shape the meatballs. Scoop about 1 1/2 tablespoons per meatball (a small cookie scoop helps) and roll into 18–20 balls. Place on the prepared sheet pan, spacing evenly.
Lightly mist and bake. Spray the tops with a little olive oil for browning.
Bake for 14–18 minutes, until the centers reach 165°F (74°C). For extra color, broil for 1–2 minutes at the end.
Finish with lemon. Rest 3 minutes, then squeeze a little fresh lemon juice over the top. Serve warm with your favorite sides or sauces.