Chicken Lasagna

1 tablespoon butter or margarine
1/2 large onion
1 (10 1/2-ounce) can cream of chicken soup
1 (10-ounce) container refrigerated reduced-fat Alfredo sauce
1 (7-ounce) jar diced pimiento, undrained
1 (6-ounce) jar sliced mushrooms, drained
1/3 cup cooking sherry
1/2 teaspoon dried basil
1 16 oz. ricotta cheese
1/2 cup grated Parmesan cheese
1 cup sour cream
1 large egg, lightly beaten
9 lasagna noodles, cooked
1 1/2 cups chopped cooked chicken
3 cups (12 ounces) shredded sharp Cheddar cheese, divided

Melt butter in a skillet over medium-high heat. Add onion, and sauté 5 minutes or until tender.
Stir in soup and next 5 ingredients.
Reserve 1 cup sauce.
Stir together ricotta cheese and next 3 ingredients.
Place 3 lasagna noodles in a lightly greased 13- x 9-inch baking dish.
Layer with half each of sauce, ricotta cheese mixture, and chicken.
Sprinkle with 1 cup Cheddar cheese. Repeat procedure.
Top with remaining 3 noodles and reserved 1 cup sauce.
Bake at 350° for 45 minutes.
Sprinkle with remaining 1 cup Cheddar cheese, and bake 5 more minutes or until cheese is melted.
Let stand 10 minutes before serving.

Note

Cantadina Light Alfredo Sauce was used and is found in the dairy section of the supermarket.