Position racks in top and bottom thirds of oven and then preheat to 400 degrees F. Line two rimmed baking sheets with parchment papers and set aside.
In a bowl, soak the bread in milk for 2 minutes and then mash into fine paste. In a small bowl, whisk together the eggs, soy sauce, garlic and ginger, and stir to combine. Set aside.
In large bowl, combine together the beef, cilantro and green onions. Add the bread mixture and egg mixture; gently stir until well blended (do not overmix).
Scoop 2 tablespoons of the meat and form into balls. Arrange the meatballs onto the prepared sheets. Bake, switching and rotating pans halfway though, until the meatballs are lightly browned and cooked through, about 20 to 25 minutes.
In the meantime, prepare the glaze by combining the soy sauce, maple syrup, vinegar and ginger in a saucepan. Bring the mixture to a boil over medium-high heat, stirring constantly, about 2 minutes. Reduce heat to medium; whisk in cornstarch mixture until sauce thickens, about 2-3 minutes. Stir in the sesame oil. Add the meatballs into the saucepan and evenly coat them with the soy glaze.
Serve over rice or on their own.