Good-Cooking - Cajun Fettuccine

Ingredients

• 1 pound dry fettuccine
• 1/2 cup butter or margarine, divided
• 1 bunch green onions, green and white parts, chopped
• 12 ounces white button mushrooms, cleaned and sliced
• 1 red bell pepper, cored, seeded and sliced
• 2 teaspoons minced garlic
• 1 tablespoon Cajun seasoning
• 1 pound frozen cooked and peeled crawfish tails, thawed and drained, or peeled and deveined shrimp
• 2 cups whipping cream or half-and-half
• 1/2 cup dry sherry, optional
• 1/2 cup shredded Parmesan cheese