Trim the fat from the tenderloins. Butterfly by making a lengthwise cut, cutting to with in 1 cm of the other side. Place in a shallow pan or zip-lock bag. Combine soy sauce, ginger and garlic. Pour over tenderloin. Cover or seal; refrigerate at least 3 hours turning occasionally.
Remove tenderloin and discard marinade. Combine brown sugar, honey and sesame oil in a small saucepan. Cook over low heat, stirring until sugar dissolves. Coat grill rack with cooking spray. Grill over low to medium heat 10-15 minutes per side or until a meat thermometer reaches 160 degrees. Baste frequently with honey mixture.