Grease 13x9-inch (3-quart) baking dish. Cook noodles to desired doneness as directed on package. Drain.
Meanwhile, in medium skillet, cook ground beef, onions and garlic over medium-high heat until beef is thoroughly cooked. Drain, if necessary. Add soup and mushrooms; mix well.
In large bowl, combine spinach, 2 cups of the cottage cheese and 2 of the eggs; mix well. In another large bowl, combine cooked noodles, remaining 1 cup cottage cheese, soft cream cheese and remaining egg; toss gently.
Heat oven to 350°F. In greased dish, layer 1/2 each of the noodle mixture, spinach mixture and beef mixture; repeat layers. Cover with foil.**
Bake at 350°F. for 35 to 40 minutes or until thoroughly heated. Uncover; sprinkle with french-fried onions. Bake an additional 3 minutes. Let stand 5 minutes before serving.