Stack 3 (14-inch) squares of foil. Fold foil in half, then double-fold 2 opposite sides to make pouch. Spoon rice, zucchini and peppers into pouch. Gradually add broth and remaining dressing. Double-fold foil at top of pouch to seal.
Grill packet 10 to 15 min. or until liquid is absorbed.
Remove from grill.
Let stand 5 min. Meanwhile, grill shrimp skewers 5 min. or until shrimp turn pink.
Spoon rice mixture onto platter; top with shrimp and onions.