01 - Preheat oven to 400°F (200°C). Line a baking tray with parchment paper or lightly grease.
02 - Heat 1 tablespoon olive oil in a skillet over medium heat. Sauté diced onion for 3–4 minutes until softened. Add minced garlic and cook for 1 minute longer. Remove from heat and let cool slightly.
03 - In a large mixing bowl, combine ground chicken, cooled onion and garlic, chopped sage, dried thyme, salt, black pepper, and optional nutmeg.
04 - Add breadcrumbs and the beaten egg to the bowl. Gently mix until just combined, being careful not to overwork the mixture.
05 - With damp hands, shape the mixture into balls using about 1 heaping tablespoon per ball. Arrange evenly on the prepared baking tray.
06 - Brush or drizzle the formed balls with the remaining tablespoon of olive oil.
07 - Bake in the preheated oven for 20–25 minutes, turning the balls halfway through, until golden brown and cooked through. Internal temperature should reach at least 165°F (74°C).
08 - Serve hot with a preferred dipping sauce or as part of a main meal.