In a large saute pan, over medium heat, heat the oil. Add the onions. Season with salt and pepper, and cook, stirring. Saute until the onions are slightly soft, about 3 minutes. Add the stock and garlic. Bring the mixture to a boil, reduce the heat to medium, and simmer for about 6 minutes. Add the rice and simmer for 12 minutes, stirring constantly.
Clean, trim and dice the shellfish and seafood. Season the seafood with salt and pepper. Continue to cook for 6 minutes. Stir in the butter, cream, cheese, and green onions. Simmer for 2 minutes, stirring constantly. Remove from the heat. Spoon the risotto in the center of each shallow bowl. Garnish with parsley.