Grease a 9x13-inch baking dish and preheat the oven to 400 F.
Make the white sauce: melt the butter in a large saucepan and saute the garlic for 30 seconds. Add the flour and cook until slightly golden brown, about 30 seconds. Whisk in the milk, and cook until thickened about 2 mins. Sit in the 4 tbs Parmesan cheese, cream cheese, parsley flakes, salt, and pepper. Cook until the cheese is melted. Remove from heat and sit in the spinach.
Make the ricotta cheese mixture: in a small bowl, mix the ricotta cheese, egg, red pepper flakes, basil, and oregano.
Layer the lasagna: spread ⅓ of the cream sauce, place 4 lasagna noodles on top, ½ ricotta mixture, ½ shredded chicken, ½ shredded mozzarella cheese, 4 lasagna noodles, ⅓ cream sauce, ½ ricotta mixture, ½ shredded chicken, ⅓ cream sauce, and ½ shredded mozzarella. Cover with foil and bake for 15 mins. Remove foil and bake 5 more minutes until the cheese is melted and golden brown.