Melt butter in saucepan; stir in flour, add 2 cups milk. Cook and stir over medium heat until thick.
Combine beans, vegetables, remaining 2 cups milk, white sauce, parsley, thyme, salt, pepper; mix well.
Cover bottom of greased 13x8x2-inch pan with 1/4 of the noodles and 1/4 each of bean mixture, ricotta, and mozarella cheese. Repeat layers 3 times.
Sprinkle Parmesan cheese on top. Cover pan and bake at 375 degrees F., 1 to 1-1/4 hours, or until noodles are tender.
Remove cover; bake 10 minutes or until top browns. Let stand 15 min.
Canned beans may be used. Noodles may be cooked before assembling lasagna. Bake 350 F. oven 30-45 minutes or until heated. Prepared marinara sauce may be served with lasagna.