Remove and discard any fatty tissue from kidney. Combine water and vinegar; soak kidney in water-vinegar mixture 1 hour. Drain well.
Slice kidney in 1/4-inch-thick slices. Combine flour, salt, and pepper; dredge kidney in flour mixture. Set aside.
Sauté onion and garlic in butter in a large skillet over medium heat. Add kidney; cook over low heat 5 minutes or until browned, turning occasionally. Add thyme, bay leaf, beef broth, and wine; cover and simmer 30 minutes or until kidney is tender. Remove and discard bay leaf. Serve over hot cooked noodles.