Preheat your oven to 400°F (200°C). Prepare a baking sheet by lining it with parchment paper or lightly greasing it with olive oil.

In a large mixing bowl, combine the ground chicken, breadcrumbs, egg, milk, minced garlic, and chopped onion. Add the Dijon mustard, maple syrup, olive oil, thyme, paprika, salt, and black pepper. Mix until just combined.

Using your hands, shape small portions into 1 ½-inch meatballs and place them on the prepared baking sheet.

Bake the meatballs for 18–22 minutes until golden brown and the internal temperature reaches 165°F (74°C).

In a saucepan, whisk together the Dijon mustard, maple syrup, apple cider vinegar, olive oil, garlic powder, onion powder, salt, and black pepper. Heat for 3–4 minutes until slightly thickened.

Toss the cooked meatballs in the warm sauce until evenly coated.

Transfer the coated meatballs to a serving platter, garnishing with fresh herbs if desired.