Heat oven to 400 degrees.
Mix together the ground chicken, egg, breadcrumbs, onion, half of the garlic and half of the hoisin sauce in a bowl, season with salt and pepper, and mix to combine.
Roll mixture, about 2 tablespoons, into balls, and place on a baking sheet.
Bake in oven for about 5 minutes, until meatballs start to become slightly firm.
Meanwhile, mix together the remaining hoisen, garlic and ginger in a small bowl.
Remove meatballs from the oven, and using a pastry brush, lightly brush the sauce on the partially cooked meatballs.
Return to oven and continue to bake for another 5 minutes, or until meatballs are very firm to the touch and cooked through.
To serve: place meatballs on romaine leaves, top with grated carrots and cilantro, and enjoy right away.