I don't know if this should really qualify as lasagne! But if you're craving the flavor and don't have the time, try this...
1½ lb ground beef (or turkey, etc.)
28 oz jar of marinara sauce
2 C cooked rotini pasta
1 1/3 C French's French Fried Onions
1 C ricotta cheese
1 C shredded mozzarella
Brown meat in a large skilled; drain away grease. Stir in sauce, pasta and ½ of the french fried onions. Heat to boiling, stirring often. Spoon ricotta cheese over meat mixture; top with mozzarella and remaining onions. Cover; cook 3 minutes or until cheese melts.