Combine chicken broth, fresh rosemary, olive oil, salt, and black pepper in large bowl. Add red potatoes, cut into 1/2 x 1/4-inch sticks and chopped green onion.
Divide mixture among four 8 x 8-inch squares heavy-duty foil. Fold two opposite sides of foil over, folding together 3 times; repeat with other two sides. Grill on covered grill 30 minutes. Or bake in 450 degree F oven 30 minutes. Makes 8 servings.