Pasta Spinach Bake

I found this recipe from Cooking Light cookbook. I added 3 eggs to the sauce. It worked very well. I posted with my changes. I cooked for the dinner party last Saturday. I was very happy with the recipe. Everyone loved it.

Ingredients

8 ounces uncooked mostaccioli (3 cups uncooked tubular-shaped pasta)
2 tablespoons reduced-calorie stick margarine, divided
1 cup vertically sliced onion
2 teaspoons bottled minced garlic
1/4 cup all-purpose flour
2 1/2 cups skim milk
3 eggs
1 1/4 cups (5 ounces) preshredded Parmesan cheese, divided
1 1/2 teaspoons dried Italian seasoning
1/2 teaspoon pepper
1 (14.5-ounce) can diced tomatoes with basil, garlic, and oregano
1 (10-ounce) package frozen chopped spinach, thawed and drained
Cooking spray
1/4 cup dry breadcrumbs
2 tablespoons (1/2 ounce) preshredded Parmesan cheese
Parsley sprigs (optional)

Preparation

Preheat oven to 350°.
Cook pasta according to package directions, omitting salt and fat. Drain; set aside.
Melt 1 tablespoon margarine in a medium heavy saucepan over medium-high heat. Add onion and garlic; sauté 5 minutes or until tender. Add flour; cook 30 seconds, stirring constantly. Gradually add milk; cook 4 minutes or until bubbly. Remove from heat. Stir in 1/4 cup cheese, Italian seasoning, and pepper; remove from heat. After the sauce cool add eggs and mix well.
Combine pasta, sauce, 1 cup cheese, tomatoes, and spinach in a large bowl; stir well. Spoon mixture into a 13 x 9-inch baking dish coated with cooking spray.
Combine breadcrumbs, 2 tablespoons cheese, and remaining 1 tablespoon margarine; sprinkle over pasta mixture. Bake at 350° for 30 minutes or until thoroughly heated. Garnish with parsley, if desired.