In a large resealable plastic bag, combine sherry, oil, garlic and oregano. Add chicken; seal bag and turn to coat. Refrigerate 3 hours.
Drain chicken, discarding marinade. Heat a Dutch oven over medium-high heat. Add chicken in batches; cook and stir until no longer pink. Remove from pan.
In same pan, heat butter over medium-high heat. Add peppers, onion and garlic; cook and stir until tender.Stir in sherry; bring to a boil. Stir in tomato puree, salt and pepper; return to a boil. Reduce heat; simmer 8-10 minutes or until slightly thickened, stirring occasionally. Add chicken; heat through.
Meanwhile, in a stockpot, cook rigatoni according to package directions.
In a small saucepan, combine cream and cream cheese over medium heat; cook and stir until blended. Add to chicken mixture; stir in Romano cheese.
Drain rigatoni; return to stockpot. Add sauce to pasta; toss to combine
