01 - Preheat oven to 400°F (200°C). Line a baking tray with parchment paper or lightly grease with oil.
02 - In a skillet, heat 1 tablespoon olive oil over medium heat. Sauté diced onion for 3 to 4 minutes until soft, then add garlic and cook for 1 minute longer. Allow the mixture to cool slightly.
03 - In a large mixing bowl, combine ground chicken, sautéed onion and garlic, sage, thyme, salt, pepper, and optional nutmeg.
04 - Incorporate breadcrumbs and beaten egg. Mix gently until just combined to avoid toughness.
05 - With damp hands, shape the mixture into balls, about 1 heaping tablespoon each, and arrange them evenly on the prepared tray.
06 - Brush or drizzle the remaining tablespoon olive oil evenly over the chicken balls.
07 - Bake in the preheated oven for 20 to 25 minutes, turning once halfway through, until golden brown and fully cooked to an internal temperature of 165°F (74°C).
08 - Serve hot, accompanied by your preferred sauce or incorporate as part of a meal.