Bring broth to boil in medium sauce pan. Reduce heat to low and cover. Melt 2 Tablespoons butter in heavy medium saucepan over medium-low heat. Add onion and saute until tender but not brown. Increase heat to medium. Add rice and stir 1 minutes. Add 1 1/2 cups warm broth. Boil gently until broth is absorbed, stirring frequently. Add another 1 cup broth, stir until broth is absorbed. Add remaining 1 1/2 cups broth, 1/2 cup at a time, allowing broth to be absorbed before adding more and stirring frequently until rice is tender and mixture is creamy, about 25 minutes. Stir in 2 Tablespoons butter and 1 cup grated cheese. Season with salt and pepper. Sprinkle with parsley and shaved Parmesan