In a saucepan over low-temperature, heat the Alfredo sauce. Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 minutes or until al dente; drain.
Boil shrimp in a large pot of water until they turn orange. Then place in bowl with melted butter. Let shrimp marinate for 15 to 30 minutes; remove. In a large skillet over medium heat, saute the green pepper and onion in a small amount of oil.
Mix together the cooked pasta, shrimp, pepper-onion mixture and Alfredo sauce. Season with garlic powder and cumin.