Cook pasta to al dente, according to package directions. Rinse with cold water, set aside.
In large bowl, combine cheddar, gouda, mayonnaise, sour cream, Worcestershire, hot sauce, pimentos, smoked paprika, cayenne and sugar. Mix well. Add salt and pepper to taste.
Add cooked pasta and mix thoroughly. Refrigerate pasta salad for at least 30 minutes before serving. Garnish with green onions.