Spinach Chicken Lasagna with white sauce

• 1 medium onion, chopped
• 1/2 cup butter, cubed 
• 1 very large (or 2-3 small) garlic clove, minced
• 1/2 cup all-purpose flour
• 1 teaspoon salt
• 2 cups chicken broth
• 1-1/2 cups whole milk
• 4 cups shredded part-skim mozzarella cheese, divided
• 1 cup grated Parmesan cheese, divided
• 1 teaspoon dried basil (try more)
• 1 teaspoon dried oregano (try more and/or just use Italian seasoning)
• 1/2 teaspoon white (or black) pepper
• 2 cups ricotta cheese
• 1 tablespoon minced fresh parsley
• 9 lasagna noodles, cooked and drained
• 2 packages (10 ounces each) frozen spinach, thawed and well drained
• 2 cups cubed cooked chicken

Directions

• Cook chicken in oil in a pan and thaw chicken. 
• In a large saucepan, saute onion in butter until tender. Add garlic; cook 1 minute longer. Stir in flour and salt until blended; cook until bubbly. Gradually stir in broth and milk. Bring to a boil; cook and stir for 1 minute or until thickened. Stir in 2 cups mozzarella, 1/2 cup Parmesan cheese, basil, oregano and pepper; set aside.
• In a large bowl, combine the ricotta cheese, parsley and remaining mozzarella; set aside. Spread one-quarter of the cheese sauce into a greased 13x9-in. baking dish (or two 8x8 pans, saving one for later); cover with one-third of the noodles. Layer with half of the ricotta mixture, half of the spinach and half of the chicken.
• Cover with one-quarter of the cheese sauce and one-third of the noodles. Repeat layers of ricotta mixture, spinach, chicken and one-quarter cheese sauce. Cover with remaining noodles and cheese sauce.
• Sprinkle with remaining Parmesan cheese. Bake at 350°, uncovered, for 35-40 minutes.